Believe her due to interactions via OC and way she handled claims and such. It's also like an incredibly provable role and we only need to start worrying if neither of the two die for a looonngggg time.
Ok the first part comes with experience as a player, I put Yeti on being careful with her words and the way she handles claims as any alignment here.
Secondly if all of our info gets leaked to the mafia NOW then if we wait for a while and neither die it's too late
That said I expected this from the way she acted during signups, like she requested a Village Leader role. The obvious fear is if she acted that way to posture and get early claims but I'm tempted to believe a mason claim for now, at least enough to give out my role name. If your rolename represents a very distinct niche as pokemon(Specifically if you are only known for setting status since we know what that does), I would urge you to be cautious, however a lot of the calculus of what abilities and moves do can only be effective when the leader gets a significant number of full claims.
The safest part of this claim is how provable a successor is once she dies, so it's higher risk higher reward for a longer lasting, more mole proof village leadership. Presumably in the coming days as inspectors or whatever weird roles could fit into a game like this(Type checkers, move/ability checkers) either confirm her and lay low or out a lying Yeti and find people they can trust, we'll be in a better position to discuss how we organize.
Belated good luck here. Happy to finally be in a Smogon Big (TM).