Presumably the CBP agent can't just check a box = pax X's GE has been cancelled??? The CBP agent must document a pax's faux pas.
A few routes to take with ombudsman:
(1)CBP agent was very rude when I interacted with him
(2))Playing "dumb", I received a notice of my GE rejection--why?
(3)Going in the other direction: "I may have questioned CBP too forcefully...I am sorry if I did."
Others reading this thread can make additional comments.