Reckon Kodax Achievement Bug

https://youtu.be/FzNMmxpBaU0
You clearly see that i was the one to knock down 3 of the runners, AND FINISHED all of them
After the raid - i didn't have the achievement in Kodax which is done by: killing 3 Runners on a reckon while using the ult... 
Clepoy#5729
Pc/Steam