Glad OP resolved issue.
We carry 25' jumper cables (surprised no ones mentioned) that reach from truck to camper which I've used once for that purpose. Our camper batteries are pain to access and remove, even if removed wouldn't fit in truck. Managed, setting 3 days at camp getting in/out of truck, newly installed electric truck steps killed trucks batteries. I now turn off steps when camped. Even if camper wouldn't start truck having cables most would offer to jump.
Starting a truck amp load is huge, hundreds of amps. Batteries dying natural old age death just get weaker until they wont turn over engine, however every camper & truck battery Ive replaced was due to battery just failing without indication.
As to towing we also had ours flat towed with front lifted, driveline removed. When calling need to stress overall weight and height so tow truck big enough sent out.
