Here is info on the restaurants and bars in the Tulum section.
By "Diamond" section, do you mean the Hacienda Club?

If you're Canadian, they sometimes call things something other than what agencies in the USA call them. The Hacienda Club section is an upgraded section on the Tulum side of the resort.
Here is info on the Hacienda Club.
You can poke around that whole web site, lots of info there as it's the offical site for the hotel.
And it's pronounced Bah-hee-ah.