The back of the camera looks fine. The GPS block pins might not have all been the same height. I've adjusted them and we'll see what happens.Are any of the GPS prongs bent? Are they all the same height?
Inspect the GPS contact area on the back of the camera. The area that the GPS prongs contact on the back of the camera should be about flush with the back of the camera. Is it depressed at all? Is it loose?
Can one buy a new GPS mount?