It's so easy to think of what we would have done if we had been the ones confronted with the family's situation on that fateful night/day. There were opportunities to help Bryce but nothing seemed to stick - the roommate, the (ex) girlfriend, Christian, LE, the phone calls with his mother. The list goes on and on. They only knew he was in the same spot for that long AFTER he had been in that spot for so long. By the time they figured that out he was on the move. It's all very sad, IMO.
Here are my two cents:
While I think that Bryce may have suffered some sort of "psychotic break" either because he was pre-disposed to doing so or because of whatever drug/alcohol combination he had ingested in the few weeks before he went missing, I don't think he was using during his 13+ hours in Buttonwillow. He interacted with people and he spoke on the phone multiple times with his mother. Someone would have noticed slurred speech, dilated eyes, agitation, smell, some errant behavior to indicate that Bryce was high (or low) on something, IMO.
I think that he was SUPER depressed. The Disappeared episode seemed to drive home that point over and over again.
I think that his parents are in denial about a lot of things but I don't blame them one bit. I think it's really hard to understand depression and addiction (if there was any real addiction tendencies with Bryce). They love their son and it shows. Was the mom's actions overkill? I don't think so given what ended up happening. She clearly knew something was awry. I don't for a minute think that she made him skip out on his life.
The only reference to Naperville that I saw was on cover of the birthday card his mom had from him. The move does seem like a significant piece of the puzzle and I'm curious why it was left out of the Disappeared episode.
I didn't realize that the truck ended up crashed that far from the water. For some reason, I had it in my mind that once he went down the embankment, the truck essentially crashed near the water's edge, like 30-70 yards. How did Bryce "walk away" from that accident when his truck did a nose-dive off the cliff and fell 25' landing on the front end? There was a little of Bryce's blood found but nothing significant.
I don't think there was foul play involved in his disappearance. I don't think he's in the water, either. I think he wandered off into the desert and has sadly passed away. Maybe he's still out there, with amnesia, drifting, homeless. But, if so, how did he get to where he is (by trucker?) and why hasn't anyone reported seeing that shockingly ginger boy anywhere? What a sight he'd be if he had long, scraggly locks and beard, right? Not a sight that would blend into the wood work, IMO.
I hope Bryce is found, safe somewhere, or brought home to his family so that they have answers. The not knowing must be unbearable.