The Nittany Lions ended their three-game losing streak by dominating the Boilermakers.
Penn State finishes the season with a 9-3 record.
Mitchell has four years of eligibility remaining.
Teams can train at Jeffrey Field and stay at the Penn Stater Hotel.
Nzeh will be searching for his third program with two years of eligibility remaining.
Carey is the second safety to join the 2026 Penn State recruiting class.