It seems that the leader was killed at night, which means he can't be the one doing the killing. That leaves the twins and the scientist. Killing with the twins probably isn't very effective, as they don't have any special abilities (unless they're noobs, of course). Blocking with the same character for two nights in a row would also be strange. That leaves the scientist and possibly the maniac, but the latter is most likely just using his first ability, or maybe not.
Oot could help out right now with his table, so we can figure things out better.