Henderson became the 13th player to join Penn State's Class of 2025.
Meiga has two years of eligibility remaining.
The Midshipmen's six-run fourth inning sunk the Nittany Lions' hopes of a Sunday victory.
Travis Luensmann had a season-high nine strikeouts en route to a dominant win on the road.
Mack appeared in every game in 2023, primarily on special teams.
Veilleux spent last season at Pitt.