Cable routing depends on where you plan to house all of your gear.
I use the cabinet behind (to the rear) of the dinette. I use this as my "Radio Shack" I have my ham, CB, my internet, and other electronics.
This is where I house my WiFiRanger "Go" router. I have a fused 12 volt
power supply terminated at a fused, HD terminal block, My WFR Go, is on the wall of the closet suspended with 3M body moulding tape... it is there just short of forever!
My cat 5 cable was a little more difficult, and challenging. For this I removed the Thin lite in the center of the roof, and breached the outer skin by drilling a 5/8" hole. I mounted the "Mobile" on my Winegard antenna mount, zip tied the cable down, then ran the cat 5 to the hole I just drilled.
Here is where the installation gets tricky....
I had to snake the cat 5 bast 2 ribs, one radially, one laterally. I then drilled another hole in the inner skin in the cabinet.
After a lot of trial and error, I was able to get everything fished, and connected. It was not easy, but the overall installation is very clean.
I had to pop a few of the rivets off to get past the ribs, and catching the other end of the ethernet cable was tedious!
It sounds like you are just going with the "Mobile" this is basically the same deal. I have a 34 footer, so that would be a long wire sitting on the roof, not sure what you have. I have run coax down the fridge vent for other applications, but those antennas are within literal inches of the vent, therefore no cable laying on the roof.
Where are you planing to install the WFR POE? You can run the cat 5 behind the upper roof lockers. There is a little ridge that will hold the ethernet just fine.
If you need more photos, feel free to ask!
I chose the most difficult route, but it is clean and invisible.
Just make sure your cat 5 can rotate and flex as the antenna moves and rotates.
Let us know how it goes!