Thanks! I ran some simple tests on my own after posting and found similar.

I've opted to go 3 Helltooth and 1 zDPS. The Helltooths will use Jeram's Bracer so they can cast Firewall 3 times. Rotation will be Fire Wall x 3, Acid Cloud x 1 (unfortunately, none of the Ground AEs stack when laying multiple down) then Corpse Spiders till all dead. The zDPS will piranado while the others are firewalling, Big Bad Voodoo while the others are Acid Clouding, then spam Haunt while the others are Corpse Spidering, and spamming Horrify when it's up.

i can do T10 slowly (not worth it) but my zDPS is missing a lot of essential gear.