After an extremely severe break in my wrist (I actually shattered it), and a surgery to attach an X-fix device for proper healing, I was diagnosed with RSD. My hand turned black, the hair on it turned black and it shrank in size a great deal. My doctor diagnosed me with RSD at that point.
I'm not sure what changed or why, but after that diagnosis, I got better. He explained to me that my injury was so severe that my mind basically "cut off" my hand and wrist, thinking that the injury was too severe for recovery.
But just when I thought it got as bad as it could (I couldn't let anyone even see my hand), it just started getting better. Today, besides some scarring, my hand is pretty much normal. I lost range-of-motion from the injury, but suffer NO symptoms of RSD (this is almost 10 years later).
Does your DD simply suffer from pain, or does she have physical changes in the area of the injury?