"Filth_encrusted container key" bug?

In the course of the early Venice missions I picked up a “Filth encrusted container key” which a good online source, Crygaia, said to use and it would provide one of three keys each of which would give a champion match at Kaida Harbor, by opening a container. But when I used the key it disappeared and no new key appeared, either in main inventory, mission items, or wallet.

I wonder if anyone else has had experience with this key and what happened to them? Or if anyone can clarify this matter?

Thanks!

It can also disintegrate into 750 anima shards. That’s where yours went.