Some are open to 3, 4 and even more! Depends on the guests. Just kidding. Think you better give TTR a call to get the real info and not get in any bind.
On the members site only the Garden View room class shows as having a maximum occupancy or 3. All other rooms are a max of 2. They may entertain a request to allow 3 in another room class but they need to fit in a 2nd bed .