score:7
This CBP page says a Sentri card holder may use their passport at a Global Entry kiosk when entering the US by air. The page goes on to state an exception: Sentri card holders who are citizens of Mexico must specifically apply for Global Entry via their Trusted Travelers Account.
Thus, if you had arrived in the US by air, and are not a Mexican citizen, you were erroneously denied use of the kiosk.
Other than pointing out the contents of the page cited above, and perhaps having a copy of that page in your possession to show, I don't know any other approach that might allow access.