Solved it myself, excuse me for being lazy and not reading correctly.
The fix was pretty easy for anyone wondering, turns out the mob only had dead UNIT flags and I had to reset them using,
me->RemoveFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_NON_ATTACKABLE | UNIT_FLAG_NOT_SELECTABLE);
me->SetStandState(UNIT_STAND_STATE_STAND);
me->SetHealth(1000);
Thanks anyways.