You stand pretty much no chance of getting standard rewards, they are simply blacked out, and too bad that you live in a NWA hub, where NWA invested heavily and will try to get out as much as possible.

Plus, NWA is not as big in MEX as AA and CO, further limiting the availability.

I would focus more attention on calling around student travel agencies and get a decent discount fare: most of those fare earn miles. If you are willing to risk it, book in the peak of the peak days, and book the first flilght, so you can volunteer at least for one flight and get some cash/voucher back.

Timing wise, you are too late in getting standard award: they might appear 100+ days before or 14 days within pre departure, while 90-21 days pre departure is the PEAK booking period, very rarely to see increase in reward inventory.