I would reach out directly to the certifications team via email (certifications-at-meraki.com where '-at-' is the at symbol) and let them know you've been trying to get into CMNA for a really long time. The program is in very high demand, but it certainly shouldn't take 3 years to get in. Depending on where you are in the world, CMNA might only come around once every 12-18 months, while in some other places it might be twice a year. I just helped teach a CMNA in New York City recently, and I can tell you that (unfortunately) there were as many people on the wait list as in the classes.
You should regularly check the partner portal (merakipartners.com) and when the next batch of CMNA classes comes your way, sign up immediately. I want to say it's usually updated monthly so watch for new classes. I say "batch" of classes, because when we run CMNA, it's 3 total classes. It's a 1-day class but it runs 3 days in a row, typically Tue/Wed/Thur, so you can pick from 3 different classes. And there's limited seating (only 15 seats per class) since you have pods of physical equipment for each lab station.
Let the certifications team know your location and they can gauge demand and try to work something into the schedule. One time last year, we actually did 2 weeks in a row in NYC, I'm guessing because there was so much demand, so we were able to get twice the number of people through CMNA that time around. I'm not on the training/certification team but hopefully this helps. Good luck.
