Gralwynn starts to paw at the corpse of the creature, looking for anything she could use (components or ingredients or some such)

Investigation 8

If there's anything thing good, she'll slink back into her elven form and grab them, if not, she'll stay in panther form.

Balmaris will lean against the wall and pull out his notepad and jot a few things down, and a quick sketch of the beast

"Does anyone have any idea what that was?"

Rynna looks at the 'door' again and tries to think if she's read anything about such a thing in her arcane studies.

Arcana 18

Nope, can't say as she has.

The real question is has the treasure-hunting bird man ever seen such a creature!

None of you have any recollection of living doors or shapeshifting mouth creatures. Rynna, what you do remember is that there are tales as old as any magic in this world that talk of mad mages and twisted arcanists that fueled disturbing creations by trying to impart life on inanimate objects. You don't recall if this is one of those, or just a bit of cunning mimicry, or what have  you.

Either way, your search turns up nothing of any expected value, just a weirdly flobby corpse.

OOC: Did Creak determine if there was anything behind the “door”

Apologies! It does in fact open into a passageway, as if a real door used to be there. The passage extends ten feet forward from the doorway and then makes a sharp left turn.

Creak gestures to the new opening, “Gotta go- somewhere fishy- right?- I think that is the best choice.”

"Lead on Creak"  Balmaris will fall in behind the bird

(OoC: did Gralwynn find anything?)

As mentioned, no searching of the corpse turns up anything collectible or otherwise useful.

Creak will lead onward through the door!

Panth-Wynn follows the ever more delectable-looking Creak

Rynna falls back into formation, ready to follow the others.  As far as she was concerned loot came at a lower priority that getting out of this strange house and seeing the sky again.  By Chauntea, she had never known how much she found solace in the earth beneath her feet and the smell of trees and grass, not mold and dead things.

Quote from 2Goblins_In_An_Overcoat >>

Panth-Wynn follows the ever more delectable-looking Creak

 Ignoring the growing sense of concern radiating off the cat, Creak continues!

(OoC: think you need to pick a direction, if we're following you)

Through the monster door opening, as I mentioned

This room is festooned with moldy skeletons that hang from rusty shackles against the walls. A wide alcove in the south wall contains a painted wooden statue carved in the likeness of a gaunt, pale-faced man wearing a voluminous black cloak, his pale left hand resting on the head of a wolf that stands next to him. In his right hand, he holds a smoky-gray crystal orb.

There are two doorways, one in the north wall and the western wall entrance you find yourselves in.

Ongoing Map:

Is there a check to see if any of us know the man in the picture?

For the statue, you could make a History check, albeit at a high DC.