In 2153, in preparation for their dangerous mission into the Delphic Expanse, Jonathan Archer asked Casey to assign a team of MACOs to Enterprise NX-01. Casey responded by assigning Major Hayes and his squad, assuring Archer that they were the best men he had. (ENT: "The Expanse", "The Xindi")
The next year, after the successful conclusion of Enterprise's mission in the Expanse, Archer recommended to Hernandez, captain of the Columbia NX-02, talking to Casey about assigning a squad to her ship, as well, although Hernandez was skeptical about having military personnel on board. (ENT: "Home")
The novel The Good That Men Do gave him the first name George.