He will undoubtedly be receiving many empty forms if they are being sent successfully. I'm wondering what this will do to his paranoia and if he will post about it.
Poe's Law is what you're looking for, I believe.
There's no reason to assume it's fake or a parody in my opinion.
Psychosis/Schizophrenia is very real and affects many people, who can function very normally but think slightly weird thoughts and have the urge to express them and tell people.
The way your post started, I thought you were going to tell me "it's not paranoia if they really are out to get you." I almost included that in my first note.
It's possible and probably worth it to mention, that he also may actually be extremely well medicated.
I am not sure what law or internet forum rule it is that says any sufficiently developed parody of being a kook is indistinguishable from being a real, honest to goodness kook... but browsing around this site I am quickly reminded of that adage.