Was Maury Terry's The Ultimate Evil Part of A Son of Sam Coverup? with Special Guest Manny Grossman

It's a fair question, but few others ruffle feathers of Son of Sam aficionados more than this. Why did Maury hold out information, even from friends, until the day he died? What do others in the Cult-of-Terry know that they refuse to let out? Why would Maury be reluctant to release this material if he was in fact the author/journalist on a mission to reveal the truth about these horrendous crimes?