I'm trying to get the sequence of events.
His vehicle was found on Port Chicago Highway near the Hwy 4 overpass. It was found with the headlights on, the motor running and had a flat tire. I don't think his vehicle was the one mentioned in the CHP report. It's not clear what time the vehicle was discovered.
His mother reported that she got a call from DL around 4 am and he was upset, too upset to drive, she said, since he wanted to come and talk to her. She was in Oakland which is southwest of where his vehicle was found. She said she would go to Pittsburg so they could talk, presumably later in the day of Jan. 1st.
So did he take her advice and not attempt to drive to Oakland? He was found on Hwy 4, but do we know whether it was eastbound or westbound?
His vehicle was on the road underneath Hwy 4 but his body was found on Highway 4 down the embankment. The area where his body was found was previously searched with canines. Do we know the date of the search? His body was found on Saturday Jan 7, seven days after he was reported missing. Bodies have been found in locations previously searched.
I believe a family member found his body. Were they the ones who mentioned his clothing was dry? I know some clothing was found at the site of his VW but what? A jacket? Shirt? Pants? What clothing was he wearing when found?
Around the time he called his mom it was raining heavily in Concord. It started raining around 2:30 am and by 5 am it was raining heavily with fog. It continued to rain heavily until around 7 am. Here's the link for that info.
Weather reports from the last weeks in Concord with highs and lows
www.timeanddate.com
If he was hitchhiking to get home to Pittsburg, visibility would have been very poor. There's a possibility he may have been involved in a hit and run.
If he died early in the morning of Jan 1, I would think decomposition would have been fairly advanced. It was mostly overcast with rain several days, with a sunny high of 17 on the 1st and an overnight low of 4 degrees on the 2nd.
The thing that really seems to disqualify him dying the day he abandoned his vehicle is the anonymous call directly LE and family to his body.