100% sure, it depends on the bank, every bank has its own policy and they change from time to time. Years ago Banco Lafise used to be the friendliest with foreigners, not any more, things changed a few years ago when a few managers were charged with laundry and they had to change policy. Go with Banco Davivienda and you will be able to open an account in US dollars. It will take a lot of paperwork at the beginning, but, after you complete that, no problem at all.