Here's what I did
The problem is that the signals and power that flow between the Tailgater antenna on the outside and the Dish receiver on the inside will not flow through the splitter that is a part of the antenna/cable/preamplifier switch and jack panel.
I recently installed DirecTV in my trailer. If your TV is located near the wall plate with the antenna/cable pushbutton, you can do what I did. I've attached a writeup describing my modifications.
"You cannot reason someone out of a position they have not been reasoned into"
Al, K5TAN and Missy, N4RGO
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WBCCI 1322, TAC FL-39, AIR 82265