If snakes could sight on relief then Val would do it. Moving carefully he slithers back to the floor and into the rat hole, trying to find them again and see of he can overhear their conversation as they walk into the new noble room. 

( Perception: 18 

Also, that "my lord" was as in formal title to the lord of the house or as in "you are my liege and I owe you allegiance type of My lord?"  

DM: Okay so about your question on what type of "My Lord" that was, how... are can you tell the difference from just hearing them? I'm not really a native English speaker so really I don't know if there is a tone differentiate between them without actually noticing body language.

Val slithers out of the rat hole. He overhears some of their conversation as he senses them heading down the hall.

Victor: "What is the issue?"
Vlad: "All in due time. Let's keep moving towards your new room for now."
Vlad (to the armor): "You! Stand guard in the hall. If you see the shape-shifting snake, kill it!"

The armor's footsteps stop as it reaches the end of the hall. As Val gets to exit of the mouse hole (hasn't poked his head out yet), he can hear the Victor and Vlad's footsteps getting further and further away as they head down the stairs. They stopped somewhere on the first floor. You aren't sure where they went after that as the footsteps become to faint to follow.

(About my lord question... I am not sure, I guess that the difference comes more from the tone and context but it's ok I agree that Val lacks of both to have the distinction clear. Can he reach the other floor via the mouse holes? if not, can he go back to his room? )

Runt looks at her hand and flexes it. If he trys anything I do not like. I will see how flexable his skull is.  If it's not clear by now, Runt has no experience with girl talk what so ever and is probably taking things too seriously. 

@Val: Actually you can go to the other floors via Mouse hole but the tunnels are more labyrinthine than the house so roll... Survival or Investigation.

@Rest of party: If anyone can confirm if you can tell the difference between the two meanings with just sound, let me know. I can make a more confident ruling that way.

(Let's try this... I got the felling that Val is going to get lost.. again ;) ) 

(Survival: 22 )

Val slithered around in the walls, scaring rats left and right. It took a while but then he realized that he was lost. Strangely he can hear metallic footsteps moving around as he slithered. Then while still having no idea what part of the house he was in, he heard Vlad say, "The shapeshifting snake is in the walls. Rats, stay alert near the mouse holes. Attack the snake if you see them."

This indicated that Vlad had some control over the rats and, based on how many rats snake Val scared off, Vlad figured out he was in the walls. After giving this comment he storms off somewhere. Val doesn't know which way he went because he can only hear him from inside the walls but not see him.

A few minutes after Vlad went away from earshot of Val, he came to the party's floor again, knocking on Val's door. However Val is not in that room but Deva is.

"Well, maybe he's putting it on a bit heavy because he's really lonely." Elsara reasons. "I mean, he lives here in the middle of nowhere, so having guests must be really novel. I was brought up in a library, so there were a lot of new people to meet." She takes her seat again where she was. "Maybe we can sort it out in the morning."

Val is going to try to go back to his room once he realized he is lost. He will try to go out away from the metallic footsteps, hopefully in a corridor in his floor, and resumes his elf form. 

Val roll, initiative to fight off the rats that block your escape.

Runt lays down, relaxed with Elsara present. Perhaps. I am new to these things. It makes me uneasy.

(To DM: Safe to assume during all of this that none of the armors walked past the guest hallway in a hurry? And that Val hadn't gotten close enough through the walls that the group might hear something going in them?)

Devarus sat on Val's bed trying to remain calm as time ticked every on by; but, while he waited, guilt would start to gnaw on him more and more. However, without proof of foulness or any intention of going without his armor to do some scouting as well, the half-drow was good and stuck in place. So at the very least, he would spend the next few minutes doing some weapon cleaning and maintance just to keep busy.

Regarding your question: Yeah, the armors didn't really pass by the party's rooms. Mostly because for the longest time only the one armor in the 3rd floor was active. It was only after Val got lost and Vlad figured out the snake was in the walls that more armors started moving. By that point, he had already started moving to knock on the door.

Also how does Deva react to Vlad knocking on the door?

(I actually missed that. Shoot. Sorry!)

Devarus startles at the noise and needed a few moments to collect himself. However, after doing so, he frowned and eyed the door in suspicion. Val... would've come right in. And as far as he knew about the girls....

He takes a breath, straightens up, and makes a show of yawning loud enough to be heard from the door before making his way over to it. Without opening he says tiredly, "What is it, Ms. Elsara? If yer look'n for Valwyrn, he went to sleep not long ago."

Deception: 11.

Vlad hears Deva and can immedietly tell something is up. He still clears his throat and says, "Mr. Daknin. This is Vladimir." His tone has a sense of authority to it. It's a lot different from the tone he takes with the others. He says, "You see, I have been told we have a shapeshifting intruder in the building. They shifted into a poisonous snake and slipped into Victor's room, no doubt attempting to assassinate our friend. I have figured out that the shapeshifting assassin is hiding in the walls. My servants will take care of the intruder. In the mean time I ask that you be escorted to a different room for your own safety."

(Initiative: 15 )

Rat Initiative: 10

Rat moves to hold Snake Val off while other rats show up

Rat attack: 14 Dmg: 1

A rat spotted Snake Val before, the shapeshifted druid could get ready, it moved in and went for the throat. However, in its haste, the rat missed.

Val's turn.

More rats are coming.

There is a moment of silence from Devarus side of the door. Then a tired sounding sigh. He looks to the weapons at his side in consideration for a second or two before finally speaking up again. "I see.. so it was you, Lord Vlad. Hmn... The offer is appreciated. And, I would remiss in not asking if perhaps we might even join in securing this would be assassin. But, in the interest of not infringing or undermining your defenses by accident in the process, as I am sure they are extensive for your living in this area, we shall remain here but on alert, as we are more than capable of defending ourselves." He expressed, before chuckling a bit.

"Once I awaken Val that is... But do inform Ms. Ruu and Mrs. Elsara, if you would be so kind." He request, and then backed just far enough away to not be caught by a suddenly opening door. Just in case Vlad chose to be forceful. Which with that in mind, he even pulled out Scattershot, and held it at the ready in anticipation of a forceful entry. Because for all he knew, Val either failed and this wishing to move them was some sort of play to catch him too off guard, or there really was some sort of megafauna spawned assassin. One looking to pick him off next, after seeing to Val. Either way, the paranoia had reached the point that asking for forgiveness over permission appeared to be a logical excuse for pulling a weapon. 

Vlad stood at the door for a bit. Before walking over to Elsara and Runt's room and knocking on the door.