Courts, particularly those in the Ninth Circuit in California, have been leaning over backwards to make politically correct decisions to the point that common sense is totally out the window. Women whose husbands were discovered to have abused the daughter of a former wife get their lawyers to exclude that evidence from a trial about abusing the current daughter because of rules of evidence, not because of the child's best interest. A probable murderer of the child's mother like OJ Simpson is granted custody of his children.
Against such a backdrop, it is very difficult to get the court to recognize the deleterious effects of abusive behavior by a divorcing spouse, especially if the abuser is a man. Depending on the judge, the courts tend to view the mother as simply vindictive, rather than take away "rights" from an adult for the sake of the child. If there is a benefit of the doubt, it it given to the adult, not the child.
Perhaps the leaker in this situation felt that the court of public opinion was the child's last refuge. For all we know, the child's best friend's mother leaked the tape. I'm glad somebody wanted the abuse to be exposed, and hope it helps the girl more than it hurts her.
What fantasy world do you live in? The courts almost always take the mother’s word as gospel.