Withey's point total tied a career high while Travis Releford pumped in 23 points for the Jayhawks (4-1), who claimed a victory in the title game of the CBE Hall of Fame Classic.
Ben McLemore helped out with 11 points and six rebounds for the victors.
The Billikens (2-2), meanwhile, couldn't follow up their semifinal win over Texas A&M with a tournament championship.
They were led by Cody Ellis with 19 points and eight boards.
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