If it is MMFO airspace, is it really uncontrolled?
I have routed from SCL to LAX, passing through what my Jepp iPad app shows as XX03 FIR (south of N05, East of W120) which was uncontrolled and borders MMFO. Entering MMFO airspace, they did expect position reports. They had HF freq's that they did not answer, and when finally contacted on SATCOM, admitted were out of service.
But if they are only a few flights, it is easy to separate them via level.