Event is on Sunday. The following link says visitor pass center is only open Monday through Friday.
https://home.army.mil/westpoint/index.php/about/visitor-information
It also has ID requirements: "Generally, a current driver’s license or passport will suffice for identification, but driver’s licenses and identification cards from specific territories and states that do not comply with the REAL ID Act of 2005 are not to be used as the sole source for identity verification to access Federal installations. A listing of the current state-by-state compliance is available at REAL ID Act Status of States & Territories."
FWIW realizing circumstances change, several years ago I visited West Point through a check point gate, and I didn't go through the visitor pass process. Just had to sign on and be off post by 2PM.