I understand the frustration of not receiving cards in the mail, and I can imagine it might be challenging to find oneself in disagreement about how to rectify a situation that was caused by the large and sometimes unpredictable middleman in the trade. There are many generous traders here, but it's true, expecting replacements when both parties have essentially upheld their end of the bargain probably shouldn't be counted on. Some send replacements anyway, others understandably wish to allow more time for the USPS to get things to the right place. It doesn't feel right to some, but unless everyone decides to trade in person, it's what we've got.
I wish you luck in your future transactions, and hopefully they'll feature a more swimmingly smooth postal service.
