There is no free cruise with Caesars Diamond. It is not a benefit. Carnival sent out cruise offers to people who had Caesars or MGM Diamond/Gold. They must have bought a list and you had to send pictures of the cards and then they added you to mailing list. I did take a comp cruise with them and only paid port taxes. That Carnval did this is not a benefit for Caesars or MGM. It was a marketing initiative.

Also, if you ever get an offer like this you are limited to the cruises they offer to you. You cannot get a comp if the cruise you want is not on the list.

BTW, Caesars offers discounts of up to 30% off but it is Norwegian Cruise Line not Royal Caribbean