Sadly, they are not part of the MGM or Caesars system. But they do have a link with Marriott’s rewards program, so you’ll earn points with Marriott. Also, Cosmo

Sadly, they are not part of the MGM or Caesars system. But they do have a link with Marriott’s rewards program, so you’ll earn points with Marriott. Also, Cosmo is fairly generous in terms of comped room offers, even for people that give them very little play. Make sure you sign up with their player’s club as soon as you get there and attach your card number to your room so you get credit for your full trip spend, not just your casino play. Charge all your meals etc to your room to get points for those as well. After a trip or two, they’ll usually give you a few free nights.