Clearly the movies exist in an alternative universe - if only reflected by the fact that giant robots can appear amongst crowds of humans and yet no one seems able to digitally record such an event (c'mon, even Warnie and Liz couldn't do that). By extension the Moon landings did not happen the same There as the they did Here.

In fact the trailer suggests that checking out the Ark was the actual reason they went to the Moon in the first place. They knew it was already there.

So as Sky Shadow says, false information about Darkside Radio Blackouts could have been placed prior to the actual mission so as to make such unusual events explainable.