Memory eater/Defeat the elder in a red map/Elder boss do not spawn

Hi ggg,

i am on the quest: Memory Eater, collect the shapers memory fragment (14/15), defeat the elder in a red map, the shaper must survive.

As u can see on the screenshot, the elder is placed in the red map "The Reef". I cleared this map, but in the end just the regular map boss was showing up, and not the elder boss. So the quest can not be completed, while the elder boss is still placed on "The Reef" map on the Atlas map screen, after defeating the normal boss.

https://imgur.com/a/5xMayPW