Inverter charging the camper from the trucks batteries.

Running 120V cable from truck to camper would be my biggest worry.
My truck has factory 350W inverter build in it. I already tested that my small shop compressor will run on it and am considering using it for refrigerator power while on the road.
But drilling holes for cable and putting safe grommets stops me on the idea.
You also have to think about "senior moment" when you can forget to unplug while unloading TC.