To me it's not a coincidence that he meets with a CL buyer, and then goes missing, is found dead 3 hours from home, without his vehicle. Odd too how his phone pinged in Beaumont, then went off and didn't ping again. I do think the CL buyer needs to be looked at hard.
Just a scenario going around in my head. The buyer shows up to look at the car, with a cashiers check for $35,000 in his pocket. Wants a test drive of the vehicle, and Abdullah goes with him cuz he's not dumb to let the car out of his site without payment. Maybe CL buyer brings a friend to help him check out the car? They go for a test drive, buyer says he wants it, gives AA the check, AA signs the bill of sale, the friend strangles him from the back seat, they drive out to Palm Desert and dump him at the Cook Street off ramp and overpass after taking the cashiers check off him. Then they drive the Audi home or go back and get the car they came in. When you think about it, either the CL buyer drove a car to AA's apartment or had someone bring him, otherwise he now has two cars he has to get home. There had to be another person involved in this with the CL buyer. IMO, JMO.