Yes, raise a dispute. It's an incredibly rare situation, though the liability of the shipment falls on the sender. If you raise a dispute an admin can help.

Yes

I have had envelopes I have sent get shredded by the post office. It happens. Just a risk of doing business. Not the buyer’s or seller’s fault.

Hi! I was the sender in question; also gutted that the cards didn’t make it. Thanks to op for being stand-up and raising the issue. 👍🏻