There are other telepaths in this castle. Use some of them.

If it was anyone else but Legato, I would have no problem with your idea, but the fact f the matter is, this isn't something we can do. Not without risking him messing with their heads and making things even worse with his telepathy.

Can you imagine how much worse the guilt your friend would have if he did something while doubly mind controlled? And this is assuming none of them are immune to telepathy.