Bowen was a member of the Penn State coaching staff for three years, serving as co-offensive coordinator in the 2020 season.
Penn State brought on Shane Eachus and Brent Zdebski just over a week after Knowles' hiring as defensive coordinator.
Knowles touched on his defensive system, reasons for coming to Penn State, and drive to win a national championship.
Tinsley spent 2024 on the Washington Commanders' practice squad.
Smith served as Penn State's offensive analyst and analytics coordinator for the last two seasons.
Mills will attend his third school after attending Lackawanna Community College before Penn State.