There is the possibility he wanted to go back into the Saudi fold, and that this disappearing act has all blown up and backfired out of all proportion.
There is so much to this story. I find it so difficult to believe that he was simply assassinated and chopped up in the embassy before being taken back to be disposed of. That's amateurish and Jason Bourne.
The Saudis may be a lot of things, but stupid isn't one of them.
If you expand the circle of influence. He was the nephew of Adnan, the arms dealer and according to wikipedia,Dodi Fayed was his cousin.
Interesting family ties he had....
Anyway. As usual, great, balanced and researched post. I hope this is what you do for a living :-) If not it ought to be!
Best wishes to you :-)
***Edited. I forgot about the Apple watch. Very odd angle