

To be fair (basically the only time I’ll say that in reference to Moon landing deniers) there are also retroreflectors like those mounted on some of the unmanned landers and rovers that have been sent to the Moon as well. So this alone isn’t going to “convince” him. It does indicate that the Americans were able to launch something to the Moon and land it at the same time that the Apollo missions were underway, so if you were dealing with a rational person who could be convinced by reason this would still count for something.
Unfortunately, I doubt that’s what’s going on here.

Not only do some conspiracy theorists not believe in the Moon, there are so many of them that there’s a variety of these beliefs.
So yeah. Poe’s Law, there’s nothing so dumb that you won’t find someone actually believing it.