To keep Bosco from getting hurt, you could give him a Kong or something so that he's occupied enough not to go there. I also think there are some other camping threads that might have an answer to your question. Enjoy your trip!
Awwww that's a real bummer! Give it a few days for his stress hormone to calm down. Slowly reintroduce the car rides, keeping them short and frequent (as much as he can tolerate without reacting in a stressful manner). Probably what you already did, but help him realize this trip was a one-off, and normally a car ride=fun experience.
Lol, that happened to us too, we rented an SUV to drive to Niagra Falls and we loved it. It was about 10 years ago and we didn't have heated seats in either of our own cars. Someone accidentally turned on my husband's seat (it was the middle of summer and very hot), and he couldn't figure out why his butt was burning! 😂😂😂
We finally figured out his heated seat was activated! Lol.
Good luck on the 13th! We'll be waiting for whatever stories you have and pics!