That wouldn't be a "bandwidth limitation" and is against Net neutrality rules. Also none of the providers in the state have any throttling or data caps especially the ones who offer video services. That may be different with cell providers but they don't tend to offer video services.

This sounds like there might be something else going on. Especially if they are trying to cast to a TV and they have adblocking setup on their WiFi and it is causing an issue with the stream since it can't load an ad or something. Happens all the time if you have advanced features on your WiFi.