How about the Kenyan Government that sent him there in the first place?
That's an unintentionally interesting angle. Obama, Sr. was present in the United States at the behest of the Kenyan government. Might the whole natural born debate be mooted by his legally recognized son being plainly excluded on the basis of Constitutional language dealing with children of foreign diplomats, etcetera?
I assume Obama, Sr. had his school expenses paid by the Kenyan government. It's logical to assume that he received a stipend of some sort as well.