I suppose Hitler and Castro must have corralled a lot of favor with the same deity in this case :D
That being said, it seems unlikely he was grazed by a bullet---too precise of an angle plus too little damage to his ear. Most likely the shock wave came within a few inches, so it would have missed independently of the direction he was turned.
(Obviously way closer than any set up would have been, but I doubt the conspiracy theorists will come to this conclusion when the crime scene reconstruction analysis comes out and probably says something like this).