An update on this: I sort of can't believe it, but this might actually work out in my favor. I did some looking around and saw that TEAMGROUP offers a "limited lifetime warranty" for micro SD cards in the same class as the one that I own. I sent them an email two days ago thinking that I wouldn't even hear back.
Today I did hear back, and rather than laughing me off, they're asking for photos of the card (to ensure it's not physically damaged) as well as details about my purchase. If they end up sending me a new 1TB micro SD card under their warranty, I will eat my hat. One of them. Only one hat.