Its tough, because the janitor had no knowledge about the wolves so we can't even really look at voting patterns. All I can think of is to see how invested people were in trying to kill the wolves. I feel like the janitor would probably try to blend into the background more and not work so hard? I would say another strategy is to confuse the matter and try to misdirect, but since the janitor had no extra info they could easily help lynch a wolf by accident that way.
The two people I trust most to be villagers are Jesse and Rowan at this point. Neither I think are 100% safe, but Jesse has helped kill the wolves the most (which doesn't say everything since if he was a janitor he wouldn't know who they were, but like I said I feel like the janitor wouldn't lynch as much) & Rowan simply because I know him well enough to feel like his relief at not having a special role is real. (If I'm wrong I'll feel really silly)
That leaves:
Dan
Donna
Kathy
Emzies
(if i forget anyone pls tell me)
Out of these, I feel like Dan fits my theory of how the janitor would react the most. He's been online but barely posted (until now, suspicous) though I don't really have much else to go on.
I think we just have to get lucky at this point. My vote is for
Dan
EDIT: I'd also like to point out that Kathy feels less invested / loud than in other games, which makes me go a little bit
but she also seems to just be busy in general, and not just lying low in werewolf only.