Me and my husband 2-man this with two different set-ups, no luck yet though.
1:st set-up: my prot pala and his druid (boomkin specced for the run). He get the mount if it drops
After weapons are defeated my pala picks up the Cosmic infuser and the Bulwark - hello self heal that gives fire resistance.
Husband picks up the Staff ofc
2:nd set-up: His blood dk and my shadowpriest. I get the mount if it drops.
I just pick up the staff.
So if you are a tank or caster (with healing) that want to try it out here is how we did it.
This vid gave us some idea of where to kill off the advisors, but we adjusted it a bit: http://www.youtube.com/watch?v=BhwzMEvbc1I
1st (slowpoke) at entrance - be aware that he indeed can knock you out of the instance, so back against the wall.
2nd (the one that fears)at entrance by the tank while the caster runs towards the doorway to Kael's room.
3rd (warlock) doorway to Kael's room, and yes she's annoying when casting conflagation.
4th (engineer) a bit down the ramp where warlock was killed off.
Weapons are killed close to warlock, staff equpped. (and pala equip shield and cosmic infuser, helps a lot in p3)
Caster goes for warlock and tank the engineer. Stay close enough of eachother so you both get the buff from the staff.
Advisor that fears is next, and last the slowpoke.
The next phase is a bit tricky, due to positiong Kael. If you look at 03:40 at the vid I linked you will see the doorway/hall leading towards Kaels' room. LoS at each side (red crystal pillar). Tank run in when he's passed the first doorway (the one with the closing beams), but not so far that the buff from the staff falls off. Interrupt fireballs, and try to stand in the other doorway (boss still LoS of the other player) so if needed the boomkin/shadowpriest can heal you.
Tank should move in (towards boss) when the big red circles appear.
The healing is also great to take aggro on the Phoenixes that spawn. The tank should only kill phoenix if tanks back is against the wall to the left in (hallway where Kael is standing). The phoenix does do a knockback when it dies, and being shot down almos the entire ramp is NOT fun. Eggs ofc needs to be killed.
If caster want's to help dps Kael, do it after he shout the mc emotes ("Bow to my will" and "obey me" if I rememer it correctly). Just remember to move back after about 10-15 seconds.
Last phase begins when Kael reaches 50 % health.
After first gravity pull, swim out towards the ramp and cast spells /ranged abilities on him. This is to minimize the damage from nether beams. When gravity pull phase is over, tank run in and interupt as many fireballs as possible. Ranged should take care of whatever phoenix spawn.
Rince and repeat until Kael is dead, and good luck on drop.