Incarnation of Neglect No drop at all

Hi,

I killed the Incarnation of Neglect along with my friend but i left the map to refill while he finished him and he dorped nothing ( Yes it was using a fragment not from the default quest ) I disabled the loot filter and there is absolutely nothing on the ground, not even a single white item whatsoever .

Update: I never had this situation before, turns out you have to be present in the map to have loot at all which is respectfully stupid.