We probably should get our terminology straight so we don't start confusing one another. The OP stated:
So basically I was saying that the killer has no idea that s/he is the killer.
It's known that only one of you is sane.And I assumed that meant only one of our roles is exactly equivalent to what the role PM stated, and everyone else had an actual role different from the stated one. I took the former to mean "sane" and the latter "insane". This differs from the traditional definition (which only applies to cops if I'm reading the wiki correctly), but it'll probably be more appropriate for this game. Unless you want to use "deluded" or something instead to avoid confusion?
So basically I was saying that the killer has no idea that s/he is the killer.