Dan, you are my new favorite poster!Fine, but I do think my thread about "Is this a plausible conspiracy theory?" - which received little attention - is simpler. Some person or persons in Mexico City suggest to Oswald that the assassination of JFK will make him a hero to Castro and ensure his entry into Cuba. Perhaps they even suggest they will be waiting, either near Dallas or in Mexico, to ferry him to Cuba when the deed is done. Perhaps it's all BS or perhaps they are sincere. It's a conspiracy, albeit not a very sexy one. Oswald remains the lone gunman whom LNers know and love.
Good effort but in order to maintain the crown I'm going to have to call "foul".
Technically your scenario isn't actually a conspiracy.
It's more like coming up with a motive for Oswald's actions than it is a genuine conspiracy.
Oswald is still a Lone Nutter.
You had me on the ropes for a second there

To me, it's just inconceivable to explain the events of 11-22 in terms of Oswald as a patsy. Even in your scenario, I can't imagine how he would have been allowed to live. Shelley claims to have seen him doing the deed, wrestles the rifle from him as he attempts to escape, and nails him at the elevator - much cleaner, it seems to me.
I would have to argue that the first thing that cements Oswald's guilt in the eyes of everyone is him leaving the scene of the crime. He is confronted on the 2nd floor 90 seconds after the shooting, which is almost as good as an alibi as no one is going to believe that a fleeing assassin stopped off to get a Coke. If he held his nerve he could bluff his way to freedom but he runs and it is this that seals his fate.
Having him on the run is crucial to establishing his guilt.
As for Shelley, he would need a cast iron alibi, so he would have to be visible to everyone on the front steps at the time of the shots. Within seconds a motorcycle cop was on the scene scuppering any chance of dealing with Oswald if that's what he wanted to do but, according to Oswald, it seems it was Shelley who told him to run along. Something Shelley obviously denied.