I wonder about this.
I had a AAA vacation in 2011. I did set up my room request through AAA, but the AAA
travel agent gave me my Disney room confirmation code and I was able to use that to make my own dining reservations. I'm wondering if you have the room confirmation whether you can just call in yourself and add your room request? Seems logical that you should be able to since you can make your own dining reservations 180+10, but I don't know for sure since I didn't try it.