Most likely, he crashed his car, walked away, got lost and died....
But based on clues left at the scene, it's POSSIBLE, he was uninjured, with full faculties, exited the car, locked it out of habit, after grabbing his backpack. In it, he might've had another device. And cash. He COULD have hitchhiked his way out of there, someone passing through, unaware of the drama since OR used another device to communicate with someone who picked him up exactly where his scent ended. He may have wandered around while waiting or those scent trails (to the abandoned house and pond) weren't his scent.
If someone did pick him up, maybe they know he wanted to walk away and start over.... so aren't saying anything.
Likely? No. But it beats the alternatives. Because it would mean he could still be alive.
JMO