Citadel Boss Bug

Bug reference- 4177329214

I killed the copper citadel boss and I died at the same time. The map says complete but I can't get my loot. I can't teleport to the second stage of the boss fight.

I don't know if citadel bosses work the same way, but on regular maps if you die to a boss, it wipes everything off the map... this happens even if you die to a monster before you fight the boss if you have walked past the boss's checkpoint... Just an all-round terrible idea