My daughter had a large hemangioma in the center of her forehead and it often took a similar appearance to your daughter's. It would get kind of gray/black and saggy and bled once or twice. After that it seemed to scab and heal back over. My little girl's hemangioma was removed at 13 months so I am not sure of the long-term effects of this scabbing process, but I know it did not seem harmful or painful to her at the time.
I hope you have received more information and feel more comfortable with your little one's situation. If I can help in any way please let me know.