What events in the opening pages of the sectio, "Answer" turns the investigation around

The reader is introduced to Floyd Wells for the first time. Wells, a former employee at River Valley Farm, was Dick’s first cellmate at the Kansas State Penitentiary, and the first to inform Dick what a “score” might be had by robbing the Clutter household. Upon hearing the news of the murders, he realizes that Dick must be the perpetrator, and presents his account to the authorities at the prison.