I wouldn't advise that you make this move without permission of the court. If the parents have voluntarily terminated their parental rights, why haven't you proceeded with a full guardianship, custody order, or adoption? It seems to me there is a step missing. If they have surrendered their rights, they may not be able to contest the move. You should file a motion or petition with the court for permission to take her with you. You might have to open a guardianship in the county where you are moving, and transfer the case there. This is a complicated situation, and there are many factual and legal issues that have to be reviewed, including reviewing the court file going back 13 years.
I was in court last weekend when this issue came up. The judge (Wayne County) indicated that the appropriate procedure would be to initiate proceedings in the County where you move and then Wayne County would close your file, once you have been appointed.
I would check with an attorney where you move to decide whether or not the parents need to receive notice. Since they signed off on their rights, then they may no longer need notice.
Best of luck to you!