Pinnacles Paired: The Elder not completed

I completed Elder with my merc. But i didnt not receive challenge (The Elder was the last missing).

I tried "/recheck_achievements" but nothing happened.

if you're talking about the favourite map slot im having the same issue, i killed uber elder twice and nothing.
i did get the voidstone tho

Same here. I cant finish this challenge, because "The Elder" never counts. I killed him a few times now. Merc is active and alive till the end of the fight, but challenge still doesnt count.

I have 6/7 of the challenge "Pinnacles Paired" so far, so the other Pinnacle Boss Encounters did count.

Is there a trick? Or is it a bug? Anyone can say something?

I finally got the challenge by killing uber elder.

Yeah i can confirm. The challenge needs UBER elder instead of only elder boss fight.

I killed both, Elder and Uber Elder with my Merc active and it does not complete my challenge...

uber elder (regular elder + shaper) worked for me

Same issue. Haven't tried ü-elder yet (I'm lazy, I know) but the challenge says elder so I guess it should count...