The easiest way to deal with this fight is bring a bard or chanter with ya and have them mezz adds. We tried to kill the adds before named popped but the instant we agro'd him they spawned and assisted. It was way to bazaar to be a respawn timer thing... we just had bard mezz the adds, he even initiated it by mezzing the 4 and hitting fade right before the mobs could react so our tank could go in and take the named w/o taking any extra damage, not that these mobs are a fight, but I'm sure those with 30k hp will feel differently.
We were able to kill his acolytes and not have the named despawn. What we saw is that he will only spawn starting at 1am game time and despawns at 5 am game time, so not much time to kill him. He may spawn at midnight, but when we saw him it was always 1 am.
killed this mob today. he has 4 other mobs around him that are on a short ranged leash, meaning 1 was close to him but not close enough to aggro normally and the other 3 were at the spawn point but only the one aggroed. he didnt drop anything but some vendor trash, also if you kill one of the mobs around him they will all despawn and he has about a 20 minute respawn. dont think the mobs can be calmed either because i calmed one and it still aggroed but that was with the monk calm which isnt really a calm its a reaction radius reduction.