Fran will turn to offer Polly help out of the water, a piggy back even if she so chose.

Was it the rule, or the personal preferences of the cultists you have met so far, but they did not keep anything of vital importance "on the job". The clothes/armour and weapon is of a good quality (though nothing special), no orders, but in the small pouch on the woman's belt along with meager 3 golds is a note "Fist Kazzira, Hiskaal payed the price" with the Bane skull as a signature. Yignath did not have gold on him, but bracers of his armour were quite decorative if you are into skulls/bones/spikes fashion. The most interesting loot from Yignat;s body was the iron key ring with seven keys on it.

Actually, there is only one prisoner (sacrifice?) and not on the altar but shackled to the wall right behind it. After the sack was removed (?) from his head, he first yelled and then lost his consciousness, and now his sickly thin body was hanging in chains like a thin white injured frog.

Polly gladly accept Frans helping hand to get out of the water. “That was some nasty business” she as she once again clean off her cloth with prestidigitation. 

Choir takes the keys off Adray's pile and tries them out on the prisoner's shackles, seeing if she can free him.  Only able to cast one more healing spell, she hesitates to use it on this unfortunate victim, lest one of her band of warriors die in their next skirmish for lack of a quick heal, but she casts Spare the Dying in the hope that it will strengthen the poor wretch.

Adray will un string and pack up the bow the woman dropped and any arrows she had.  As for the other weapons he'll leave.  He will then focus his attention on the doorways while the others tend to the men.  Hed hate for them to be caught un aware in their surroundings.

(Would the bracers give any ac bonus?  I know there are some magic bracers out there help provide ac for those that cant wear armor but if it's just cosmetic or its considered light armor then I'll forgo them.)

(No, that bracers are just decorative, no magic, no AC)

Choir managed to find the key from the shackles among those 7 and helped the prisoner to the floor (with some help, I supposed - the prisoner is an adult man). The movement and Choir's care gave some results - the prisoner opened his eyes again, though, when he saw kenku he made another high pitch scream and tried to fall back to unconsciousness. Unsuccessfully. Eventually, he did realize you are not cultists and from that moment stopped screaming and begun pleading. He was not dying, and though cut and bruised and definitely exhausted, could stand and most likely run. But he obviously too terrified to hope for any meaningful conversation.

"Jhasso... Klim Jhasso! This is my name! I am a noble - you have to know! A noble from house Jhasso! Second son I am! I will pay to you! My father will pay, I swear! Just help me to get out of here and come with me or later - yes, later - to my hose and you will be payed, I swear! Please, help!"

Polly walks over to the man and offer him some water,  only to realize her water pouch must have fallen off in the water somewhere (don’t have one in my equipment).

“Someone, please give the man something to eat and drink. He is on death door here.” 
“We will get you out of here, don’t worry. What can you tell us of these guys? Are there more of them? I know it is hard, but we must know.” 

She turn to the others. “We must get him out of here. It’d be to dangerous to take him with us and we can’t leave him here..” 

Adray looks at the frantic man with discerning eyes.

Incite check to see if hes truthful. 18

Choir offers the prisoner water and food.

The man does look pathetic in every meaning of the word. Sure, 2 days of imprisonment in the filthy dungeon and after constant beating, cutting and what's not - such treatment would shake dignity of most men, but Adray begins to suspect there was not much to begin with. It feels like the name is indeed his, and even in that condition you can recognize a man, that did not work a day in his life but used to the life of luxury, so he must be a noble indeed, but every time he mentions money or reward the eyes dart aside, he twitches and probably does not believe himself.

But he is genuinely scared to death and absolutely not used to prisoner/sacrificial lamb treatment.   

For some reason (probably black feathers?) Klim Jhasso was uneasy around Choir but took both - food and water - as hungry/thirsty man would. He even managed to mumble some "thanks" through the mouthfuls.

He tried to be helpful - you can practically see it on his face, that he would turn himself inside out to give as much information as he can - but he knew very little. "We were at a tavern - Blushing Mermaid - they have a good wine there, Berth said," the man speaks frantically, with nervous little scream sometimes. "And Berth said, he will pay - and he never pays! I had to see it - you understand? He is my brother, the third one. And he never pays. Olaf too was with us, and he said we need to go to the bathhouse, and there will be... a good time. You understand? But there was not! I do not remember any good time, I fall asleep in the tavern. And I woke up here! And that woman - they called her Kazzira - she was laughing at me. Such menacing laugh! And then that guy with his backet-helm - he was poking me with the spear. It was horrible! And they say they will kill me? For their God? Something like there has to be sacrifices, all the time. And they killed some of their own too - I swear! If they do something, like loosing a prisoner. Oh... And there was something strange here too - I did not see but I heard. Someone was screaming, and something was flying by me back and forth and beating that screaming man... I felt it and heard it. And they were laughing, and then commanded that to stop."

He looked at each of you very intently with whole face expressing nothing but hope that you are satisfied with the information and will help him out of here.

"Well shit, looks like you were set up.  Your brother took you out drinking, spiked it so you passed out and sold you out to the cultists.  You run home and you'll only be putting yourself back in danger if he's about.  My guess is he has somethin to gaining you die.  Anyways, you be better off taking your coin and laying low or paying someone for protection..  but probably not us.  We have to clear out what's down here.  Its job one. " he says and casts a glance at Polly, "but we can prolly get you to the entrance."

Fran would be keeping eyes and ears open, focusing on every entrance and exit, still all while holding Polly. "I appreciate the information sir." This comment directed at the prisoner.

"An' I hate teh be a stick in the mud, but I imagine they know we're here."

Ordrag sits nearby, listening and wiping his sword, and says: Sucks to be you, bro! No hard feelings, but you ain't our number one problem. 

Then turning to the others he said: Our orders are to find the cult and wipe it out, and not to get hung up on collateral. If this fella can get himself out, that's fine with me, but rescuing him ain't part of our orders. 

Information - again, practically visibly - processing by probably not much of a brain there and Klim finally drops his hands in a jest of complete despair: "No. No he would not. What do you mean - sell to cultists? What cultists? These cultists? They are cultists? Yes, may be.... But NO, no, he would not. Even Berth. Or Olaf. No?..." As pathetic as he is, right now he evokes more pity than disgust - practically naked and crushed both physically and morally now. The part about going somewhere alone in those catacombs he probably did not even hear.

Map so far:

The west passage from D9 might go back to D5. Shall we try that way?

Or do we want to peek in the south door from D9 first? 

Probably don't want to venture south or east of D12 yet though, right?

Polly sighs. She knows that her teammates are right, and this is how things are done in Baldur’s gate... bit it feels so wrong. They can’t just abandon this guy. 
“Hold for just a moment” and she takes out pen and paper and paint a quick map of how to get back out of here. “If we’re not taking you to safety, at least I can give you a map of how to get out of here..” She gives Ordrag, Fran and Adray a look of disgust but don’t say anything.

Ooc: Maybe we should commit to explore the Bane corridors before explore the other gods corridores? 

Choir scratches her head.  She doesn't think this guy will be able to read Polly's map in the dark. Most likely he will blunder into the wrong room, people will ask him how he got free, he will blab--he seems like a blabber--and bring the whole place down around their ears. The only choices she sees are to take him away, or slit his throat right now.

"You go on ahead, I will catch up," she says in the voice of an old lady traveler. She takes the prisoner by the hand and leads him back the way they came, as quickly as he can move.  If she has to, she can piggyback him out.  She may be small, but she is pretty strong. And she's pretty sure she can find the others again...she knows the noises they make.

Klim compliantly followed Choir - may be because of the light, the idea to be left in the darkness in those wet corridors should be terrifying to him. It did not look like he would cause any troubles to his guyed.

The rest of the party is left in the light of two torches on the walls and oil red lantern outside in the corridor.

Watching their Kenku walk off, and feeling the disappointment in Polly's body language, with a sigh, Fran would follow Choir with the gnome in tow. Never split the party...