What you see on Hyatt.com is what you will pay* and this rate is included all the tax, so there is no additional surprises that you should worry about.
Here is our experience with Ziva Cancun and the rate required prepayment at 14 days out.
1) Family with no status, their credit card was charged in full per T&C and in USD.
2) Me with 24 hrs cancel policy due to status, hotel didn't charge me 14 days out.
Instead, they charge me the USD equivalent in Peso when I checked in and I got hit one more time with my credit card company's rate and I ended up paying way more than the family.
Also, on points earning, hotel deduct the tax portion from Hyatt.com rate to calculate your base spend.
This definitely isn't very transparent... I've been burned before on foreign exchange when the check in agent charged my card in USD instead of the local currency leading to nearly a hundred dollars of exchange rate loss on a multi-night stay.
I guess my only remaining question now is if globalists will actually pay the price shown on the website subject to currency exchange or if there is some resort fee baked in there that means globalists will pay less.