I still think his truck was never at MM20, & that SC told Charli to drive him straight down to Jaws (on the presumption that he had gotten his truck stuck there), where she was met with harm
. Under this scenario, he most likely would have been able to simply walk or bike (he would have driven the bike in the back of the truck) home before calling Charli.
Perhaps he knew beforehand her cell provider's coverage was poor in that area, thus not having to worry about the possibility of LE being able to confirm her having been there, should there be an investigation.
Under this scenario, he could have done everything on his own, IMO: He could have driven the body in her SUV somewhere close-by before setting it aflame, gotten back into his truck, scattering various evidence along the highway -including Charli's cell near MM20- & abandoning the poor doggie in Hana before returning home & finally texting Charli's cell (he had to wait until he got home to do this because he had -intentionally, to avoid being tracked- left his cell there).
Yet, the fact that Charli's SUV was found flipped on its side makes me think there had to be an accomplice(s); even with the device that I spoke of (with which one can rotate the body of a vehicle 360 degrees) in one of my previous posts, he still would have needed help loading the device onto the back of his truck, unloading it, loading it back & somehow getting rid of it afterwards. I think the SUV's doors, parts, etc. -& even the rotating device- were used to pay the accomplice(s).
It almost sounds as though SC obtained the truck solely to accomplish this "task." My understanding is that ownership had not been transferred to him from the seller yet -that it was somewhat of a "rent-to-own"-type deal; maybe he had no intention of keeping it in the first place (thus getting rid of possible evidence in a way).