I believe this is a bug that has been around for a while. Essentially, if you loot a chest of all items except the legendary component item (Elementium gem clusters, in my case) from a chest, the chest disappears before you can withdraw them. The GMs have no ability to rectify this mistake and there is absolutely 0 warning that this happens, nor should it happen in the first place.
If you’re going to allow this bug to persist, at LEAST give the gms the ability to give people items that were lost. I know your database has a record of all loot drops, if a specific raid ID can be linked with proof of the loot being destroyed, i think it is reasonable that a GM should be able to reimburse people.