I use a freight forwarder based in Miami FL and over the years I've have a few items go "poof!" The first time it happened, I asked them to assist me filing a claim with USPS. They went "Naah, waste of time, you are just on the phone for hours!" They allowed me to file a claim to their insurance instead. Took a while and obviously wasn't convenient but I didn't lose anything in the end. I hope everything works out for you.
Mark
Mark