Fergus:

”Found them—they are over here,” calls out Fergus as he moves into the room.  He doesn’t crowd the creatures, but he does try and talk with them, asking, “Can you understand me?”

If they make noises that seem like a language, he will cast Tongues and try to speak with them.

Persuasion:  21

If not, he will cast Calm Emotions and try to deescalate the situation.

Animal Handling, maybe?:  8

Quinn slowly approaches the room to the south, shield at the ready and Lightbringer helping to light the way. While Fergus deals with the flesh nuggets, Quinn focuses his gaze on the skeleton and the statue in the southeast corner of the room. 

Perception check: 17

DM: What condition is the skeleton? Clearly it's dead, I hope, but does it show any signs of damage? Burns, crushing, lightning. etc? How about the book and the statue any signs of elemental damage, soot, etc?

Boona talked low and serious with the boys, " Do you want to ride on Karst?"

"Uh, yeah!" replies Pip to Boona, enthusiastically. "Does it bite?"

Meanwhile, Quinn examines the skeleton from afar. As far as he can tell, this dwarf died relatively peacefully – there's no sign of violence here. The skeletal body is intact (albeit long-dead), the book and quill look as if he had been writing in it shortly before his death, and the shrine (to Dumathoin) looks perfectly tidy and intact. The skeleton is lying on a wool blanket, stained with decay.

Fergus tries to puzzle out these two alien intruders. They don't show any signs of understanding Fergus, nor of speech. Nor are they remotely humanoid (a requirement for Calm Emotions.) He instead crouches to try to project calm, the way he might to a scared animal. 

But it doesn't work. Instead, both tiny creatures fling themselves at Fergus.

Roll initiative! (Fergus and Quinn roll normally, Bryony and Jorzu at disadvantage, Boona and Jurgen next round.)

Alien Gemmules: 21

Fergus:

Just as he was realizing most of his spells are entirely unsuited for these creatures, Fergus is taken aback when the flesh nuggets go from hiding and cowering to attacking!

Initiative:  4 plus see below

”They are attacking!” he calls loudly.  Fergus and all allies within 30 feet who can see or hear him get an initiative bonus from Tandem Footwork:  7

(Halfling Luck Reroll adding in tandem footwork:  18 )

Roll initiative! 

Alien Gemmules: 21
Fergus:  18 

(Quinn may add +7 to his initiative roll due to Fergus' Tandem Footwork.
Bryony and Jorzu roll initiative at disadvantage, being in the next room distracted and out-of-visual, but may add +7 to their rolls, thanks to Fergus.)
Boona and Jurgen must roll next round, assuming word reaches them above, unless other circumstances arise.)

Quinn's initiative: 28! (19+2+7 from Fergus' Fancy Footwork)

Quinn rushes towards the flesh nuggets and attempts to target the one that Bryony shot earlier. He widely swings Lightbringer, missing the first go around, smashing into the table. He takes another swing and finds his mark.

Attack 1: 7 (NAT 1 + 6)

Attack 2: 21 to hit for 12 damage OR 17 damage if target was NOT at full HP.

Quinn will Sap his target and it has DISADVANTAGE on their next attack.

Jorzu 

Foot raised ready to take a step into the ancient bedroom, Jorzu hears Fergus shout. He spins towards the sound of his friends voice and rushes towards it. "Oh dear" he he says as he instinctively reaches for his bead pouch.

Initiative 12

Quinn steps forward, and swinging his glowing mace, smashes one of the nimbly bouncing creatures (the one Bryony hit earlier) on his second swing, sending it cartwheeling off the wall. (It is bloodied - if that's the right word for something that oozes black, smoky foam instead of blood.)

The sapped creature kicks off the table and toward Quinn's throat:

Gemmule #1: Psychic Slam Melee Attack vs. Quinn: 21. Hit: 18 psychic damage.
Regardless of whether it hits, Quinn must make a DC 14 Dexterity saving throw. On a failed save, it attaches to his neck. (This is its bonus action.)

The other creature goes after Fergus, both with a psychic slam as well as an attempt to latch on, leech-like, to Fergus' cheek.
Gemmule #3: Psychic Slam vs. Fergus: 18. Hit: 22 psychic damage.
Regardless of whether it hits, Fergus must make a DC 14 Dexterity saving throw. On a failed save, it attaches to his face.

A third one appears from the east room, perhaps sensing its comrades' change of plans. It attempts to slam and attach to Jorzu:
Gemmule #2: Psychic Slam vs. Jorzu: 18. Hit: 14 psychic damage.
Regardless of whether it hits, Jorzu must make a DC 14 Dexterity saving throw. On a failed save, it attaches to Jorzu's forehead.

Jorzu and Bryony may act next. Boona and Jurgen, hearing commotion below, may roll initiative.

Fergus Dexterity Save:  12

Dex save: 23

Quinn reels back from the psychic attack, but he regains his composure just as the thing lunges for his throat. Quinn parries the attack with his shield.

Fergus:

Stumbling back a step or two and staggered by the power of the little creature's attack, Fergus casts a spell to try and help himself and his allies (Aid), and then says to Quinn, "You've got this!  Finish that one off!"

(Level 4 Aid casting to increase current and maximum HP of Quinn, Fergus, and Jorzu by 15.  Bardic Inspiration to give Quinn a 1d8.  Unarmed attack from Agile Strikes used to try and push the creature off his face!  Shove Strength or Dexterity Save DC is 14 (8+3prof+3dex))

Boona Initiative- 12

" Bite? No, only bite grass and plants."

She called Karst closer so they could climb up Karsts hairy/mossy hide, then swatted at her head as she heard noises below.

Boonas forehead scrunched together.

" Holes are also for rabbits......and badgers.....and sometimes bugbears...and stupid drow....."

Feeling in need of more points of view she turned to the boys.

" Would you like to be a stone?  I'm not sure....seems peaceful...."

( She is a little too distracted by the vagaries of lithic existence to pay much attention to below.)

Bryony Initiative - 22

Bryony had just moved to follow Fergus into the southern room after agreeing with Quinn that Carp and Pip should remain above and keep watch. He found the strange little flesh creatures, but they moved to attack him almost immediately!

"Aw crap," Bryony mutters, unsheathing her blades again and leaping toward the little aliens. "These things really creep me out." The halfling attacks the nearest creature with her blades.

Shortsword: 22 to hit for 7 damage

Dagger (w/ Vex): 14 to hit for 6 damage

Sneak Attack: 8 damage