Fighting Copper Citadel Boss, Game Crashed, Map Failed

I was in the middle of fighting Jamanra, everything was fine, there's no reason I was going to lose, got unexpected D/C, log back in and the map has failed.

I have been playing this game a LOT, haven't seen this happen before, but wow, this is totally garbage.

Disconnects happen, but saying I failed a critical map because of it? Utter BS.