The rear tire is less dangerous than the front to have a sudden blowout. That being said though, changing a rear tire almost always means discovering several more problems in the process. The Cubans across the street had a file, and we were able to use a Torx wrench to get the screw out.
Once out, the guys filed two sides of the screw, making it possible to reinstall it with a flathead screwdriver. As we are migrants here, I don't want to invest any tools I will only use once, so that's why I was gonna attempt to weld the screw to an allen wrench with some JB Weld. Luckily I avoided this potentially messy solution.