Until rulings of such government are in direct conflict with God’s laws.
Are you suggesting that going to public school is a violation of God's laws?
Which of God's laws are violated by obeying a court order to go to a public school?
How do you know it isn't God's will that this girl go to public school.
She loves to witness to everyone she meets. Think of all the people she will meet. If she is as strong a Christian as she appears to be, then she will be mightily used by God as a witness to the heathen.