The outages mostly happened at very specific times during the hour (:29 and :44) for 17 months. It just doesn't add up to being RF interference, especially from a radio tower. But if OP has a radio tower 50 feet from their home, I guess we could consider it.
How did you know when the radio tower was transmitting?
The value here is “triage experiment: try an older modem”. If it reveals something, now they’re not stuck. If it fails in the same way, no knowledge is gained.
According to the article (again), he was using his own Xfinity-approved modem. I doubt his neighbor was also using the same model.
There's no point in performing random experiments if you've already ruled out those causes in some way. It would also require either renting a modem temporarily or buying one.
How did you know when the radio tower was transmitting?