Corrupted Nexus complete but no Atlas Points.

I've had this happen twice now with nexus boss fights and not got the atlas points.

One thing that stands out is when you kill the boss there is no animation for removing the corruption. Also when you leave the boss area the minimap is reset although the map layout is the same.

The run I just did I had a unique strongbox in the map and saved it until after the boss in case the strongbox killed me and used one of my portals. But when I left the boss room it was gone, as was all the remaining mobs in the map.

The mission was not completed in my quest log. "Complete a Tier-5+ Corrupted Nexus" however I did it with a Tier-15 map and the nexus was irradiated from the tower next to it.

Similar situation happened to me. T15 boss in Vaal Factory I did die first attempt but killed him 2nd attempt. No corruption boss spawn but the minimap shows cleared