On alaskaair.com, the following message appears:
AeroMexico is a SkyTeam member. Including seasonal destinations, AeroMexico serves 13 American destinations from Mexico City.
From Mexico City, you can connect through Mexico, Central America, and South America. The South American destinations:
Delta is the American member of SkyTeam, so I went to delta.com to see if Delta miles can book AeroMexico award space at the moment. I found this itinerary on October 18 from Chicago to Buenos Aires on AeroMexico flights.
If Alaska had access to AeroMexico award space, the same exact flights would be 45,000 Alaska miles. I searched for the same flights, and just like Alaska’s website promises, they are indeed unavailable.