These stories are all "according to intelligence sources", they can really anonymously brief out anything that serves their needs.
All this requires is to understand who died shortly after Stuxnet who could have feasibly been involved.
It was his family who said that he started panicking, so he was probably involved.
The point of killing someone over some wrong they did you is publicizing it after the fact. If you don't take credit for it, it doesn't have any deterrent power.
Or alternately, he did it and then tried to back out of the deal. Now arranging an apparently accidental death then became the best way to keep security intact.
The one theory that makes no sense is that they intended his death from the beginning.
Like the JFK assassination theories that involve killing off an additional dozens of people. You can't cover up one murder by involving an extra 1000 people.
- Foreigner
- Engineer
- Married to Iranian
- Access to plant (Alleged)
- Died from non-natural causes within 2 weeks at age 36
The various deaths associated with Putin are a counter example here. Russia denies involvement but the method usually makes it pretty obvious. Rare poison, unlikely situation etc.
The asset in this case wasn't known publicly and the method of death makes people assume it was simply an accident. Unless they did some private announcement, no one was deterred. If it was Iran and they wanted to send a message, they would probably have to out the asset publicly and/or make it clear that it was an assassination. e.g. a bomb would send a clear signal that it was more likely to be a nation state assassination and not some accident or a random robbery/act of violence.
It seems much more likely that he actually did die in a random motorcycle accident (not uncommon), or he was entirely uninvolved and a dead man was chosen to pin blame on in order to hide the real method(or, to make Iranians stop trusting foreign contractors, making them do everything in-house with higher costs and worse quality).
If he panicked after the Stuxnet attack, as his family is reported to have said, then it's likely he has behaving erratically and was fearful for his life.
That could easily translate to circumstances where he rides a motorcycle in a particularly dangerous manner - e.g. fleeing from someone he thought was Iranian/Dutch/US/Israeli intelligence (even if they weren't).
Also, reasonable chance this entire story is fabricated and this was done a different way.