Something seems to stand out in all this; he was a pretty ordinary Marine back then (they were ALL characters) and he wouldn’t have been noticed except for his “defection”. My guess is that he was recruited by the CIA for his sojourn in the USSR.
Based on no evidence whatsoever.
All evidence points to him being a narcissist and a communist sympathizer.
If anything the evidence points more towards him being recruited or groomed by a foreign intelligence service like the USSR’s or Cuba’s.