Nelson has played in 31 games in three seasons with the Nittany Lions.
Wormley played six seasons with the Nittany Lions and started 42 games.
Despite the losses, outside hitter Will Kuhns posted 25 kills over the two matches, including a career-high 13 kills against Lewis.
Mills played 13 games, primarily on special teams this season.
Dennis-Sutton is the fifth Nittany Lion to announce his return for the 2025 season, along with Drew Allar, Zakee Wheatley, Zane Durant, Nick Singleton, and Kaytron Allen.
Penn State will now search for its third defensive coordinator in as many seasons.