Did a little more checking for you... the Marriott in Aruba is not available for a reward, but room there at that time start at $145 and are available....
There is reward availability for your dates at the Curacao Marriott, Cancun Marriott and the new JW Marriott in Cancun. (Cancun is great, by the way, and the JW is a brand new hotel.)
Looks like someone will be able to have a great anniversary celebration. And yes, it does appear that there is much more availability this year as far as reward travel in the Caribbean.