Also, the Birth Certificate that he provides must show someone else for a father.
That is a separate issue, and I wouldn't want to bank on the courts seeing it correctly. I've talked to a LOT of lawyer types, and they are virtually unanimous that being born a citizen is the same thing as a "natural born citizen."
If the courts see it the same way as most of the lawyers i've talked to, then it is over and the other side won.
My point is, there is a very extensive belief among most Americans and Most Lawyers that just being born in the country makes you a "natural born citizen." It takes a great deal of research to learn that this view is incorrect, and i'm pretty sure none of the judges likely to be involved in such a case will have ever seen any of the research, and will very likely dismiss it without even looking at it.
I think it is an uphill climb to pry judges off their predisposed notions about being born in the country making someone a "natural born citizen."
The smartest thing to do is to contest everything. Contest his eligibility due to his father being a Foreigner, AND contests his eligibility on the basis that he hasn't conclusively proven he was actually born in this country. I'm suspicious that he can't even prove he was born in Hawaii. I suspect his original birth document is just a handwritten affidavit of home birth, most likely written by his Grandmother, Madelyn Dunham.
If all he has as an original record is a handwritten affidavit, and no non-family member actually witnessed the birth, it will be very difficult for people to accept this as conclusive proof of Hawaiian birth. He BEHAVES as though there is something wrong. Therefore I suspect something *IS* wrong.