On the back side of your antenna switch plate there should be 3 coax cables. One from the roof antenna, one from the convenience center cable input, and one going to the internal cabling to your TVs. Determine which comes from the roof antenna, disconnect that one, and connect the cable direct from your new antenna to that point, and you should get signal to all your TVs (with the switch in the correct position). If your TVs work like that, then your cable from the roof antenna is probably bad.
Antenna switch box should look something like this one.
https://www.amazon.com/Winegard-RV-7...=1521833305414