If we can find ONE ITEM of proof that NASA faked anything in space, we can logically conclude that the WHOLE THING IS FAKE.
(I've seen many dozen such proofs)
Just like a man who is caught in ONE LIE is a LIAR and you can no longer trust him. Ditto for someone caught stealing. You can't trust him with money anymore.
Because the logic is water-tight:
WHY would NASA fake or lie about any aspect of the moon landings? If they had a technical hurdle, glitch, malfunction, etc. why not COME CLEAN about it and TELL US *before they are caught* that they had to CGI or stitch something together? But when they let us THINK it's real/live, and we catch them, well that's called CATCHING A LIAR IN HIS LIE and then you have proof of shenanigans.
Then the big question arises: WHY are they pretending that some space missions took place for real, when they were staged underwater? What else are they lying about?
Logically? I'd say ALL OF IT. It's always cheaper to film something in a desert somewhere, than to go into Low Earth Orbit, much less the Moon and do the same thing. If they are "up for a lie" -- willing to lie to the public -- then they're going to do it a lot more than once!
It's cheaper/easier to remote control a rover in Greenland than it would be to send a rover to Mars.