As a freshman in 2022 he appeared in five games and took a redshirt. In 2023, he became a starter on the offensive line and started all 14 games for the Broncos, earning second-team all-Mountain West and second-team freshman All-American by the Athletic. In 2024, Casey started all 14 games for the Broncos and was named first-team all-Mountain West and second-team All-American by the Athletic and Walter Camp Foundation.
Personal life
Casey met his wife Kiersten Van Kirk, a volleyball player at Boise State, where they eventually got married in 2023.