OK, I just went out to their web site. FWIW, I am Plat and it comes up as Non-smoking 2 Doubles not available.

If 2 doubles is your main priority (which it sounds like it is), they do have 2 Doubles Smoking or 2 Doubles (smoking preference not specified) available. You could always leave your booking the way it is and call reservations and see if they can get the 2 Doubles part confirmed, and then if non-smoking becomes available, perhaps you will get it. Or you could change your booking to just 2 Doubles and in the comments area request non-smoking room, that way the 2 Doubles would be guaranteed. Good luck.