Funny you assume he's talking 25man especially since he didn't specify either way.
OP stick with Thorim, if sanity is an issue the raid needs to be more aware of whats going on managing Malady and Brain Links properly, not looking at the "skulls" in the brain room, getting out of the brain room in a timely manner. The fights still a challenge but nothing you can't handle with your gear if people are paying attention.