I guess I'm dense but I don't see any way of answering your question without knowing what RV you own and where is/are the antenna connections, do you have a B.O.M.B. is your antenna a powered antenna or a static antenna? The floor plan would be helpful too, with the existing TV's location and the proposed location for the second TV.
For example, if you have a batwing with the PCB in the head and a power switch in a box, you won't need a splitter, almost all those power switches have one input and two outputs.
Can't give you a reasonable answer without some more info.
By the way, in my rig I have block foam insulation and it has channels cut in the foam for the wiring, can't poke too many holes in that and get anywhere.