That’s definitely your problem, the brake booster is waking up all of the modules eevrytime it applies the brakes and the brake lights light up. You NEED to add a charge line off your motorhome 7 way plug to the battery of the raptor, be sure to use a one way breaker as well. This will keep the battery charged up while driving.
if the battery gets too low, it will begin resetting the various modules on the truck and resetting them……..when this happens to the transfer case module the tcase goes back into 2wd and now the rotating wheels are spinning the tcase, transmission, engine crankshaft, and all the engine internals. You will have major issues at that point.
I have flat towed my 18 for probably 30,000 miles over the past few years….some drivers were over 12 hours….and I have never had a dead battery. The charge line is exactly what you need. I also do not use the OEM a tail lights for brake lighting, I use a basic tailgate light bar as my “trailer lights”. I just didn’t want to cut into my LED tail lights, I also am using the air line off my motorhome to apply the trucks brakes via the brake booster. On a Diesel motorhome you should have a line at the rear in the engine compartment just for this use.