Ekbab, Ancient Steed quest item did not drop

I killed the boss namely 'Ekbab, Ancient Steed' 5 times until now, and the required quest item did not drop, this issue happened after the last update was released.

I cannot continue progressing through the campaign...!

Please assist.

Thanks in advance.

As my minions were killing the boss, I was not getting the quest item, thus I used Gravebind rope cuffs unique gloves (which counts any enemy killed in my presence to be killed by me instead) that made the quest item drops at last!.