Definitely doable with one tank. We actually had to use our Bear for the tank instead of Pally as he lacks an offspec. As long as the Pally has Clemency you're good to go
2 healing seemed the way to go as well. It's STRESSFUL, but only having 2 mazes was almost a necessity as a few raiders were. . . lackluster with this.
As far as tips go, the eye adds from dispelling the debuff aren't THAT bad, and if it means saving someone do it. Also having your Ele sham save his Ascendance for the walls is amazing, they obliterate them with Lava Beam. You can life grip people through walls assuming they're trapped.
EDIT: Forgot to mention, our Mage was still damaged by Parasite even while in Ice Block, so as far as I'm aware immunities don't work on it.