Patch 0.3.1 Corrupted Nexus Boss not Spawning

I died once to a normal boss on a tier 6 Corrupted Nexus map. After I killed the normal boss, map objective was stated as completed, but Corrupted Nexus did not spawn a Nexus boss and the map was empty. Please review and fix this bug. Thank you in advance.

Same thing happened to me on two corrupted nexus maps. Died once and the map essentially resets to like a regular map without quest progression and Atlas points reward. Other bug reports about this issue don't have any official responses or fixes.