Your thoughts on Night 5 seems quite possible. In fact, I'll have to say that I agree with you 100%. I doubt a mafia would target one of their own, hence Leila was their main target for last night. As for Setzer, he is likely the target of another killing faction, maybe it's an SK, but who knows. You have brought up a possibility of a 2nd mafia earlier, have you not? How can we know there's more than one mafia to deal with?