"We thought the Kardashian arrangement, or marriage, was a terrific thing for him because it's a family, a structure, something that would give him support," Jackson said on "The Seth Davis Show," referring to Odom's marriage to Khloe Kardashian.
"Maybe it wasn't," he continued.
The first part of the interview ran on Oct. 28; the second is scheduled to go live Friday via the website CampusInsiders.com.
"Everybody that's been close to him in my group ... cannot get through to him," Jackson said. "No one can get through to Lamar, basically I think he's thrown his cellphone away."
Recently, he was arrested for a DUI charge.
"We're very concerned about him," Jackson said. "But I understand things are looking up ... so I'm really hopefully that will happen. Basketball has been his life and without it, it's a very destructive course."