The problem is, South American teams are signing up to compete in North American specific tournaments, where the rules clearly state (more often than not) default server is USE, and then they start trying to ask for the tournament / teams to cater to them. Let me try to use an analogy: The LA Galaxy (futbol team) sign up for a league / cup to compete in Brazil, and then ask the Brazilians to play in Los Angeles, USA. They would probably get ridiculed and mocked by Brazilians and the world alike, it just simply won't happen.

Honestly, something needs to be done about the South American scene but I'm not entirely sure what. They need more LAN experience, but that is nearly impossible to get because they can't qualify for any LANs (exception being NoT at Summit 2). Imo, if they want to take this seriously, their teams should invest in getting a gaming house in the US, or Europe (obviously US would be cheaper) and begin scrimming / playing matches on equal pings. Once this is done and they get some ok standings, MAYBE tournament organizers will consider having 1-2 slots for South American teams, but until they start showing results, no one wants to give a slot to a South American team where a better team from another region could've taken their place, not to mention the entire Dota 2 community / tournament organizers already assume South American players are terrible (which they are by global standards, not their fault though) and/or cheaters (give your thanks to UG for basically ruining the credibility of your scene).

TL;DR: If South American teams want to be taken seriously, they need to get a gaming house in North America, scrim with teams like EG (if they even want to) or FIRE etc. and see if they get some better LAN / tournament / league experience for someone to MAYBE consider having South American qualifiers.