I just got back to my hotel room and found a note from the manager that says:

We sincerely apologize to hear that your request to have your food items microwaved was not met by our gallery hosts. There was some confusion regarding Hyatt Place policy in utilizing our specialized kitchen equipment for the purpose of re-heating food not originating at the hotel. Your feedback served to bring this issue to our attention to properly serve you and all our other guests going forward. We strive for first place service and will immediately address this issue with the staff.