The other thing about that Holmes nonsense is that if Oswald suddenly reversed himself and started singing like a canary about his trip to Mexico City, wouldn't they have asked him something? I mean this:
"That's great that you want to tell the truth about your trip to Mexico City, and we're all ears, but would you mind explaining: why did you lie in the first place? Because: no one was accusing you of committing any crime in Mexico City, and no one said it had anything to do with the murders of President Kennedy and Officer Tippit. So, why did you lie?"
I would have wanted to know that. Wouldn't you? Wouldn't Attorney Belin? So, how could the whole movement from denial to admission occur without any explicit explanation? And I mean at the time Oswald supposedly said it and at the time that Belin and Holmes discussed it?
It's just part of the other-worldly Twilight Zone that is the JFK assassination in which nothing seems right- not the events, and not even the discussion of the events.