With some investigation they will know when the DC meeting ended. Also he could have bought a “pass” rather than a ticket. The difference is the pass can be used for anytime from two locations. A ticket only for a designated time between the locations.
And I'll bet the buddy John spoke with about sports via email on the 28th...knew John's tentative plans for watching the Army game.
Still drives me nuts that John didn't call his wife, or his kids or a buddy...and that he just didn't go home. Why spend a whole day in Wilmington??