Call the staffers at the MOC office and ask. 20th c. technology is very useful for these situations.
"Hi, may I speak with a staff member with the Service Academy nomination program?"
"I am John Zoomie, an Air Force Academy candidate for the Class of 2021. I am fortunate to have received a nomination from Representative Smith, thank you again. Are you able to tell me what method is used for his slate, in terms of ranking? Can you share with me where I stand?"
Be prepared to be told "no, we don't release that." Gracious thanks are in order, no matter the outcome.
Before calling, review the MOC website to see if the method is noted there. Read USAFA Admissions nom pages again, and the stickies here on the SAF Nominations forum, so you are clear on the methods currently used.
Finally, think about why you need to know and if it's worth calling. If the slate is unranked, USAFA just cares you have a nom and will evaluate you according to its criteria. If it's ranked, ditto USAFA - they will note the ranking but evaluate you independently. The principal nomination method is a bit different. I think the USAFA policy is such that if you are triple-Q'ed and are the p-nom, you should receive an appointment.
That's is what my DS got when he contacted one of his three nomination sources. They wouldn't share the ranking. Which is probably best to not know. I told him if he learned he was number one, his expectation would be an appointment would be forth coming, but that is not a guarantee.