I had hoped it was just a cable issue.
You have another camera that still connects to your PC. The card in it reads fine most of the time. You put the other card in and it can't read the pics. Have you tried hooking up that camera with the other card to the wife's PC? I'm not an expert, but I seem to remember years ago that not all cameras supported each others card format. I could easily be wrong on this.
Just a thought and that's about all I got.
Good luck!!
Tom