As I made the ability for Mayuri in DAL's game I'll explain it.
After 6 players dies, you can activate the ability.
You get a list of 3 players where one of the players have killed.
If you guess correctly, that player will be reg killed (I wanted a superkill but it couldn't be).
If the player survives, it means it can kill and has BP. Hardly Town role.
If it misses, it means one of the other tow killed. Meaning we most likely have a scum out of 2 players.
The player who uses it just needs to come out. And that's something that I would expect I think if the role who gets it is Town.
Second part is that yes. But luckily worst case scenario it just fails. Best case scenario it kills scum.