Then that person would have deficiences in other parts of his/her resume. But it's entirely possible to get rejected from a US Medical School, despite a high MCAT score. There's actually a reason why medical schools spend vast amounts of student and faculty time to select future students. If it was just the MCAT score that mattered, things would be so much easier.

Still, I think the main and indisputable fact is that NOBODY who wants to work as a physician in the US would voluntarily pick an offshore school over a US medical school, if given a choice. And very few, if any, would choose a new and unproven school with licensing limitations over an established Carib school without such limitations. Fairly obvious, really....