OP is Plat with Marriott so that status should be good for at least continental breakfast at the hotel. Given this, focusing on the cost of dinner seems reasonable.

I hope OP has either a printout or an email confirmation showing that breakfast and dinner is included. However, a rate including dinner is unusual in most locations, the exceptions being resorts that offer half board plans. Also, when dinner is included, I would expect to see details about whether it's buffet, fixed price menu, or some maximum amount toward a la carte ordering, which hotel restaurants are included, and also whether beverages are included, including possibly some specified quantity of house wine. In fact, I would normally ask these questions before booking such a rate.