Bugged room fight
In case Laj's room is bugged, there is an easy way to kill it without aggroing the bugged mobs.
Aggro Laj and run back to the previous room, and begin DPSing Laj right after it crosses the doorway. After a while it will teleport back to his original position and will come back to the "fight room". As a warlock I placed Curse of Doom on him and since the fight took more than three minutes because of teleporting and running back, it had a chance to hit him 3 times. So dots help a lot in this fight. We had non-elite lashers coming to the room from time to time. Just DPS those down. The major downside of this strategy is after Laj is dead, his spawns are still standing in their original spawn position and you remain in combat. This means you have to run in and DPS them fast (since there might be several lashers on one spawn point) or wait until they despawn after five minutes or so.