As probably many people know, some loot from Chief is good or bis, like the 2h epic and the leather head.
None wants to do the event to open the gates to the last boss because you need to wait 3 min after you clear the first wave of mobs.
And the respawn of the bosses have a chance to not happen. Happened to me last run (2 hours ago from the time of the post).
Please, make the mobs come in waves and better timed to prevent bosses to bug.
Its already a pain to find a group that want to do the last boss and then the event bugs and you lost 10+ minutes (and then the group probably end there).