Audio/video/pictures/souvenirs can be faked. If one were to ask someone with these (for any situation) "what separates these from someone presenting these where there may be potential for suspicion that any were faked", whatever the responder says that demonstrates the standing of the source material would raise it to the status of first-hand support.

The Cold War was, to use a metaphor, a period where everyone was seeing who can pee higher on the wall, filled with many top secrets, goalpost movings, lowered morale, and governments finding new reasons to tax people (Carl Sagan's CD album currently floating in space took many millions of tax dollars to produce and put there, many things would've taken more). It's technically "not impossible" they went to the moon, but everything given to support it does not support anything aside from what amounts to agnosticism on the subject. Some people believe the moon landing happened. I respect these people. Some of us, however, are in doubt. Around the same time the landing was said to have happened, Carl Sagan said "extraordinary claims require extraordinary evidence", and while I would give quite a bit more nuance/depth/complexity to the quote (for one thing, "extraordinary" is relative), what we have been given in support for the landings was not extraordinary in a strict sense.