The FBI investigations would have made for good cover - yes?
Doesn’t make any sense. If he was hanging around domestic communists legitimately, he wouldn’t have been working for the CIA. If he was infiltrating domestic communists, he wouldn’t have been working for the CIA. Domestic communists were infiltrated by the FBI, but if he was working for the FBI, he wouldn’t have been investigated by them for years and years.
The only thing that makes sense is that he was an actual communist. It’s freaking common sense, I mean, he raised his daughter as a communist red diaper baby. People pretending to be communists as part of some espionage job don’t do that.