Not sure how these will fit into your travel goals but...

American seems to have a lot of service for S. America..citigold checking account can add 50k with a little bit of work and you can make the min spend real easy on another Citibank platinum (can get a 60k match) by funding the checking account with it if your existing platinum was ever converted to elite. add in a citibiz and that would provide plenty to top off your AA account for S. America

chase united and united biz are both 50k + right now.

British airways has a 10k if you can do the 20k spend