Trade Partner AWOL after receiving my card

Hello!  I am interested in what the community thinks about my case.  I sent a rather expensive card to a user.  The card was insured with USPS and had signature confirmation.  The card was signed for at the end address, but the user has gone awol.  It has been two weeks since the card was delivered.  I looked up the user via the whitepages and found that he/they were using a slightly different name than the one I sent to.  They were using a shortened version of the real last name.  Do I have a mail fraud case?  This looks like it could be the user trying to hide their real name, but I'm not sure.  I have a dispute open with the deckbox admins, but it has been more than a week with no communications what so ever.  Any thoughts or comments are greatly appreciated!  Thank you!!