Hi Brireey1600,
First thing to do is bypass all the RV wiring to make sure the satellite equipment is working correctly. Run the coax from the dish directly to the receiver and the receiver directly to the TV.
After you get everything working, then introduce the RV wiring to the equation. In your Universal Docking Center (UDC), you probably have 4 coax connectors along the top. One pair is for the living room and the other pair for the bedroom. Usually the right-hand connector of each pair goes to the pre-wiring for a rooftop installation, which you're not using. So you'd connect to the left-hand of the living room pair. The coax connector for satellite in the living room would go to your receiver. But you may need a power inserter inline either at the UDC or in the living room.
If you intend to have receivers in both the living room and bedroom, you'll need a Directv splitter in the UDC. In that case, note the connector marked for power because the power inserter voltage has to flow through that connector on the way to the dish.
The UDC connections for our 2011 Landmark are pictured below. The other picture is a more recent Landmark 365 living room setup. Yours is probably similar.