Regional dedicated servers will never exist because
1. They need money and as i noticed, sometimes we have trouble paying for our already existing servers.
2. We don't have enough South Americans in community to keep the server filled and make the payments worth it.
3. If majority of people move to SA servers, others will issue huge ping problems. I do realise that some people from America or other distant places have those issues on EU server aswell, but that is the most suitable server location, as 80% of players are from Europe (or Eurasia).
P.S. Russian servers only exist because they are free and as you can see, no one plays them. Ever
SA server is online right now, we just need the rewards 😀