I don't disagree, but if this clue is to be believed, Ment is a neutral player who is dangerous to both the town and the mafia, meaning there's no point in covering for him for any of the players.
The mafia is more likely to know his role, and if he's a serial killer, then it makes no sense for them to save him, but if he's a mafia member, then it's very much worth it.
So, Kosh, you can now be safely written down as being in the mafia, because this statement "Ment is a neutral player" only suggests the opposite and that you decided to try to save Ment.

Барон "Vampires"
Отдай свои прошлые сны,
В сомненьях себя обрети,
В бешеном танце душа кружится!
Не думай, что будет потом,
Здесь и сейчас мы живем,
Стань хоть на миг сам собой, слышишь!