I only needed the disney reservation number to book the fastpasses for our lunch at Be Our Guest restaurant all the fastpasses and anything else I have done I was able to do using the Virgin reference which they sent me automatically before the fastpass booking time. Once you have the Virgin reference you can sign in and it shows you all your booking details and that was where we chose our magic bands.
Not sure if the above helps. BOG is short for Be Our Guest, staying on site enables you to get a lunchtime fastpass and you can also choose your menu if you want to.