The evidence in question is shaky at best, but even taking it at face value, it's evidence of...something. Our limited understanding and ability to collect and categorize information, perhaps. It's quite the stretch for it to be evidence of aliens, particulary of the kind that can be covered up by a government conspiracy. The whole theory is based on incredibly shaky foundations - we struggle to define what is sentience(what if we're not sentient? what if stars are?), what is life, whether there even is life in the solar system, what that life would look like(why would it use spaceships?), whether it would be even detectable with our senses and apparatus, and many more questionable assumptions to arrive to our concept of aliens "visiting" us.
"Somewhere in the middle" would be "yeah, I don't know what causes that, but neither do you" - that leaves us pretty much nowhere, very very far from aliens.