Here’s the one question I would ask. Knowing what we know of Oswald, would Russia or Cuba trust him to shoot Kennedy with a rifle from six or seven stories up (since the road declines as it approaches the underpass)? After all, he missed Gen. Walker which was an easier shot.
For the most part, Oswald was a loser and a screw-up. I could see him being set up as a patsy and I can see him doing the assassination totally on his own initiative but I don’t see a foreign government using him as some rogue assassin. He’s too undependable.
Besides, who was sent afterwards to shut him up? The Russians? The Cubans? No, it was the Mob.
I concluded that there were two conspiracies. The first was the plot to shoot JFK, most likely from the Mafia, and the second was a conspiracy to cover up the crime by FedGov because LBJ was afraid of the trail going back to Russia or Cuba, igniting a potential nuclear war. The second conspiracy probably didn’t know about the first conspiracy but they had to make damn sure it didn’t ignite a war.
IMHO, I do not think it outside the realm of possibility that the mafia could have colluded with elements of the fedgov/deep state. Both had strong interests in taking Cuba back from Castro, and getting rid of Kennedy.
I don't necessarily think LBJ was complicit, but he certainly didn't object to the outcome.