I doubt if we’ve heard the whole story on this. How he came to engage on some job in Iran...has never been fully explained. I would imagine there is some type of Iranian ‘mafia’ connection to this whole story, but I can’t imagine how this would all connect up.
I think the original story had to do with him investigating cigarette smuggling on Kish Island. And yes, there may be some sort of Iranian ‘mafia’ involvement, as well as speculation that Russian mafia may have tipped off the Iranians.