After re-reading more at length, I think you are correct about this. Therefore it is relatively of little value. The court did not even address this issue in dismissing the case.
It does beg the question though. Why would JOHN A. BARRY's Attorney make the argument if it was widely known to have no merit? It also begs the further question, why was John A Barry permitted to keep his son from this same marriage, but not the daughter? Presumably, as far as the law is concerned, what should apply to the one, ought also apply to the other.
He was being paid to take a side, and had to argue something.
Which is more excuse than Birthers have. They make preposterous arguments for free.