Per Wiki:It's official. Well, it's on Wikipedia and it doesn't get anymore official than that. (Sarcasm)
"In January of 2021, a report surfaced that Walters was among three finalists to join Bret Bielema's new staff at Illinois. The other finalists were reportedly Oklahoma State defensive coordinator Jim Knowles, and Arkansas defensive coordinator Barry Odom, Walters' former boss at Missouri. Odom eventually elected to stay with Arkansas, and on January 6, 2021, Walters was announced as the new DC for the Illini by insiders on IllinoisLoyalty.com."
(Okay, I embellished a bit, but the Barry Odom stuff wasn't in the FootballScoop article, was it?)