Ok, two setups both will work
One: Run a brand new install of RG-6 (Get quality low-loss cable) from wherever you install the Sat Receiver (LNB) to any handy outside connection.. If you can get into the utility run (usually a runner along one floor) you can easily get from there to the wet bay, odds are from there to all the bays on that side of the RV.. ANd there install a "GROUND BLOCK' type connector.. Label it Satellite Antenna and you are done with that part:
Now we have options.
Option 1, Run a 2nd length of cable back to the bay nearest the Cable in, This is the RF-(To TV) out on a Sat receiver so equipped.. This will give NTSC grade tv (Old analog) to all TV's in vehicle if connected to cable in and antenna is turned OFF (Assumes wall plate, Box of Many Buttons, (BOMB or Matrix switch) Instructions follow.
Option 2: On the back side of the wall plate are 3 connections.. One (the center one) is park cable.. Extend that to OTA IN on Sat receiver and run RF (To TV) back to that port..
Truth table
Sat receiver off.. OTA antenna (wall plate) off: Park cable
Sat Receiver on, OTA off: Sat TV
ANT ON: OTA Television (direct broadcast) condition of Sat should be off
NOTE: on the "LOCAL" tv use HDMI or A/V (Red, White, Yellow) to connect to Sat receiver.. This allows the rear TV to be on ANT (or Cable) while watching Sat up front.
BOX OF MANY BUTTONS:
This one is easy... Just feed the RF out (TO ANTENNA) to the Sat INPUT on the BOMB. Push buttons as needed, No changes needed.
And again, Direct HDMI or A/V to the "Local" television.