Defeat the Maven - Favoured Map not working

I was in a group doing Maven for the completion to receive the favoured map unlock and atlas voidstone.

Maven died and I was able to retrieve the voidstone and allocate it in my Atlas. It boosted my maps as it should, but when you hover over the voidstones it shows that I have 'NOT obtained' the stone and it did not register my completion on the left column for the favoured maps.

Any suggestions / help? Am I going to be forced to run Maven again?

Location: Absence of Mercy and Empathy

Not sure if the image below is what you needed for the /debug.







Edit: was able to get the favorite map slot and true completion on the second run. Unsure why the first bugged out.

Was the same here. Only the second kill was registered by the game.