Well, go ahead and send an email to support@eventide.com with the serial number of the PitchFactor that you're trying to register.  (It should start with PF-).  For safety sake please take a photo of the serial number with your phone or what not and send that, because if it is still registered to your cousin, we'll need that to deregister it.  If you let me know you've done so on the forums, I can take care of the problem a bit sooner for you.