What I got from the article is that he was an informant for a brief period in the 1960s and 70s, not all the way up until his death.
He was an informant for nearly 10 years in the 1960s and 1970s according to the memo I-Team showed that is from sometime between 1978 and 1988. This doesn't mean he was reactivated in the 1990s or 2000s like many informants have before.
