All the evidence points to the fact that we did. For example Russia and other countries having the capability to know while it was going on whether we did or not. It's really not something you can hide and thus pretend that you did.
There is no doubt that the launching of the Saturn rockets could not be hidden, and in space they could be tracked by radar. Ultimately the proof is the >800 lbs of rocks and dirt that was brought back. Microscopic examination shows it cannot have been produced on the Earth. Also there are the reflectors left at the landing sites.
They'll just say that Russia was in it to, along with all the other governments in the world. Or that they're just telling you those are moon rocks, but they select who can study them. Or that the reflectors were put there by robots sent there.