You don't HAVE to retake the GMAT, but if you could raise your score to 690-700, it would greatly increase you chances at a top ten schools. That does not mean you wouldn't get accepted with your current score. The applicant pool from Latin America is much smaller than other pools so that is in your favor, as is your work with a Big 4 consultancy.

Before retaking the GMAT, you should be sure that you have identified specific weaknesses that can be corrected. Simply doing the same thing you have been doing all along is unlikely to change your score. You might consider a tutor who can look at your performance across all questions types and identify leverage points.

If you are not committed to going to school in the US, you might look at the Spanish schools. IESE, IE and ESADE are excellent schools with outstanding international reputations.

Good luck,