I have to disagree with this. There are surely canons involved, but we cannot divorce this question from dogma. The Great Commission is not just canon law. Evangelization is not just a canon. We are called to evangelize our children and be their teachers in the faith not just because it is a law, but because we are compelled by our faith. If we believe what we say we do about the Lord, His Church and all the faith, then we could never in good conscience do less than all possible to raise our children in the truth. And we could never intentionally take on a condition in life which we knew would preclude our ability to do that. Parents’ love for their children is greater than that for themselves, and what kind of Catholic would leave the Church so that they could marry a particular person? And yet they would put their children in that state for the same? And all because it is not dogmatic to believe in the true faith, but rather only according to the law. No, I just don’t see that at all.
However, what you are leaving out is that in this situation the reason there was not a Catholic baptism (meaning one with the Catholic liturgy and the relevant promises, and not that there is more than one baptism) is because the Catholic parent intentionally decided to enter into a marriage in which they knew they would not be able to provide Catholic sacraments to their children. That really doesn’t actually offer a cause for an exception. If a woman chooses to marry a Muslim man, having already been told that he would forbid the children be raised as anything but Muslim, she cannot later pretend that she had no choice in the situation. She chose when she married. Her children’s life outside the Church and in a false religion is on her conscience all the same.
I do not disagree with your first statement, but I can’t see any connection to questions of social class. Any condition in which a person is unable, by no fault of themselves, to fulfill the law the penalties are not applied. If you are actually trapped in an avalanche on Sunday and cannot attend Mass you are excused from the requirement under the law. You don’t have to be a royal, but just truly impeded. And the problem in this proposed situation is that there is no impediment at all, but rather a very deliberate choice by the hypothetical Catholic parent to marry in such a way as to prevent any hope of raising any children in the Church.
But (and this is where we see the dogmatic implications of this situation) we are told, because they are going to be royal children then there is no evil in raising them outside of the faith. That means that being an earthly king has as much value as does the faith itself. Just consider the impact and meaning of that for a moment, and let it sink in. We are not talking legal things here, but deeper truths about the Church, faith and salvation. This suggestion really, really bothers me. If I can be dispensed from raising my children Catholic because they will instead be rich and powerful then the Church is a lie, and all that she proclaims is null and void. Salvation is a sceptre.