I wanted to comment for all of the non-iPhone users. If you get your SetSail pass but don't have your room assignment, GooglePay may not prompt you to add it. You can still see the number underlying the barcode by using a barcode scanner app. I took a screenshot of mine, then used an app to read the barcode from the image.
We're 84 days out and don't have our official assignment, but we have a room from the barcode. That room does not appear to be available to book on RCCL or through our travel agent, so I am assuming that it is indeed reserved for us. I'll be sure to report back when we get our official assignment!