Common, very common… He's not crazy, he's just getting swept away. He'll be fine. You don't have the force, he probably just took both blue and red pills.
Play along but do not ENTERTAIN. What I mean is if he starts getting loud remind him of infiltrating vs invading. He may believe he is in on the inside but just remind him he isn't because he is in fact infiltrating "Their" coms or what ever. Basically grab him by the shoulders, spin him around three times and send him off walking in what ever direction you wish. I assume you know more about the topics Q has raised than he does so it should be pretty straight forward. Ask him for help with something he kind of knows like say ask for help gardening or with the car but doesn't really. Remind him he doesn't know shit.