It sounds like you've got some serious networking experience. I can't say I have a surefire solution, but it's definitely a puzzling issue. Perhaps there are some quirks in IPv6 settings or how it interacts with your devices. Maybe someone here has a workaround. Also, you may find a guide to solve it here: https://onlinetvcast.com/guides/how-to-watch-fubotv-in-mexico. Good luck!