Hi Christian, I feel for you in your frustration; I had a couple of similar issue years ago and I guess it has happened to a number of collectors.
Fortunately one of them was "only" a much common and cheap one (a Lexibook Chessman Elite); the second I don't even remember which model it was (meaning I swallowed the frustration ). Don't put much hope in any carrier support to retrieve it: once lost, it is lost for good.
Grüße,
Eric