This is a very easy fight that requires only single target DPS and one tank.
All Abilities information pulled from parsing data.
After around 3 - 4 people go through the portal from the Switchmaster Zaxlyz's Room
Absatalius will spawn.
Drag him to the top left wall and place him up the top melee dps jousts the Nether Cloud to at least min distance.
Stunning Blaze is interruptable and should not be too worried about as long as you keep CoB.
Curing the noxious is critical. Otherwise, DPS / Tanks will die.
The tank responsible for 1 mob, super easy, stay alive and keep aggro.
Have a monk drop ASAP as soon as it dies to FD up the stairs.
If you can kill the first 2 mobs in the zone, your raid force should be good enough to fight these mobs.