There are two ancient MMORPG rules which do not want to go away it seems and might apply to your disappointing experience:
- Never release/revive if you die during a boss encounter unless it is a wipe. Because if you are outside the instance when the boss dies you may be locked out from receiving any loot. And many games might even prevent you from re-entering the instance during the encounter.
- Never loot a corpse with valuable shinies, until everyone who died during the encounter is alive and near the corpse, or they may not get the loot window.
Of course this does not solve your actual problem at all, nor might it help anything to workaround the actual bugs of the loot system in this game. But noticing many posts about bugged loot, I felt the need to remind people anyways.
Heck, rule one might even still be true for any MMO in existence which has instances, combat and loot. I know at least of one who is running since over 7 years and just tried to fix that problem a few weeks back.
In my opinion, it should be a highest priority to make sure players cannot be screwed over their shinies in loot centric game like this. With loot centric I mean that the power of a character is mostly defined by gear which will be looted from mobs or received via quest rewards (including commendations), or by crafting, etc..