GPS jammers are also used by truckers, rental car drivers, etc., and they have stopped airplanes before:
https://www.cnet.com/culture/truck-driver-has-gps-jammer-acc...
It's also something air defense teams would use to try to redirect missles (make them miss their mark because they have to rely on less effective navigation matters)
On the other hand, radio transmission is relatively easy to locate, and ham radio operators do it for fun ( https://en.wikipedia.org/wiki/Transmitter_hunting ) ... so it should't be that hard to find a source.