"Okay professor boring. Way to make rotting shit through the power of being pissed off, sound really fucking lame." He may play dumb, but he understood enough to realize that all he has to do is agitate this guy and he'll start spewing necrosis everywhere. Score. His own personal skeleton key.

That he can't touch. Or get too close to and have all his skin fall off or something. He leads them up to the generator door and a locked, heavy metal door nearby.

"Tried to open this one a few times. It's by a generator room so gotta be something good in there right?" Or it's generator supplies, either way maybe he can coerce a favor out of someone in return for them. Everything is an opportunity just waiting to be taken.