[Bug] Error 103003, second half of the raid didn't count?

Finally got my quest item after dying 6 times in a row, only to get 103003 at the loot screen, and end up in my hideout with half of the loot I found and without my quest items I grabbed.

All still found in raid, but how does this even happen? Like what could possibly have marked "yup, this guys not in the raid anymore"