This is a common ploy used by timeshare sales people - The sales people lure people into buying by telling them they can rent their extra weeks for big bucks - it's just not true.
Travel to Mexico is depressed, and there is a glut of Mexican timeshare rentals on the market. Right here on TUG, we have rentals in our classifieds for $1 at nice Mexican resorts.
This "rental company" will take your money, list your timeshare for far more than it will ever rent for, and that will be the last you ever hear from them. They have no intention of renting your TS - they make their money from the upfront fee.
If you are still within the rescission period, you should definitely rescind, because you can literally buy timeshares in Mexico for $1.
If you feel like you were defrauded, you may be able to get out of this deal, even if you are past the rescission period, which is 5 days in Mexico. Profeco is a legitimate government consumer agency that helps consumers. They aren't fast, and you will have to be VERY persistent with them, but they can help.
Here is a brochure from Profeco, the Mexican consumer protection agency.
We also know that people that complain loud and long on the TUG Mexico Forum are often contacted by Mayan Palace and offered a resolution, because the company doesn't like the bad publicity, so I am going to more your post there. You will want to respond to this post and explain exactly how you were mislead by Mayan Palace to have the desired effect.
Good luck!