Yeah, anything on MW from Chile would be nary impossible to get from North America. For one thing, it's a very long distance from here. Secondly, you have a lot of high-powered competition coming from Central and northern South America. Thirdly, I suspect that many broadcasters in Chile are dealing with transmitter issues right about now. Tried numerous news (normally reliable) websites from Chile yesterday and almost all were down. This earthquake did a lot of damage to infrastructure.
Frankly, I think you have to be somewhere south of Lima, Peru or SW of Sao Paulo, Brazil to have a shot at picking up Chilean MW signals with anything less than the best of equipment - and that's during the best of times.