That could work. It'd be OK flavorwise, although it might make more sense to bring back the automanifestation mechanic from TarkirWolf 1 (but not the "if you target a manifested player, you'll always hit somebody else" thing).You could make Ugin immune to non-lynch deaths, like Bolas. Then it'd turn into a game of "Let's get a majority!" over "Let's get a ma- Hey, we've won!".
Seriously though, man, I like Tarkir's roles. You just need harsher win conditions.
Alternatively, I could just make Ugin be immune to the wolfkill. That way, in order to win without a majority, Bolas would have to find and convert an Acid-Spewer or Lightning Shrieker, which might take as long as it would for Sarkhan to find Ugin on his own.
Hmm, maybe I could buff Sarkhan as well (by letting him have two targets, maybe?). If he could find Ugin more quickly, that would give the village a better chance of winning.
Thoughts?