What make and model of motorhome do you have? The newer ones are coming with external WiFi and/or cellular antennas. That would be my guess for the thin one.
Yes - the King antenna is for TV only. [ I left of the 'HD' part as it'll pick up standard def broadcasts too. ]
No markings on the antenna? Is there a connector on the inside? Maybe take a picture of that.
It's skinnier than the WiFi booster antennas I have, but that doesn't mean all that much. Someone smarter might be able to have you measure the length of the antenna and determine whether it's right for a 2.4GHz or 5GHz signal.
You mentioned satellite. I'm pretty sure it's nothing satellite related. I'm still leaning towards a cellular antenna.
Ok, thanks everyone. No markings that I can see on the antenna. Inside there are connectors for a satellite which previous owners had and the King antenna connector.