For those of you who haven't seen it yet, here's a video of Raegwyn soloing the Scarlet Monastery CM.
Solo Challenge Mode: Scarlet Monastery - YouTube
The interesting part is the mind control part of these NPCs (1:40 Timestamp).
Frenzied Spirit - NPC - World of Warcraft
These ghosts gain a stack of this buff for every attack. So what you want to do is stack a lot of small attacks against the mob, mind control it and let it tank the boss. You can repeat this for the entire instance. Free the mob -> attack it -> MC it again.
Just saw this one today, it helped my group a lot for the challenge mode. Have fun with this.