This evening there was a server crash and rollback on Scourge. Before and after, some players, (myself included), were having Steam auth issues and losing roles.
In my case, my backpack had been reduced to the non-vip size, and in the remaining slots, only a few of my backpack items were there. Before I had a chance to do anything, the server crashed and rolled back.
After the rollback, I logged back in to find I still didn't have my VIP role. I hit "Loot All" on my backpack hoping to recover the missing items, and the items that were in the whited-out slots. Only the visible items in the small backpack slots (only the items I could see) returned to my inventory. I placed all these items into a Large Box, and restarted the game.
Upon game restart, I regained my VIP role and full backpack, which was now completely empty. This means that every item that was missing, or in a whited-out slot when I lost the VIP role, is now gone and not recoverable.
Unfortunately I only have a screenshot of my empty backpack available, but I believe there may be others in a similar situation.