Why the founders changed the language, or what they thought it meant, is an interesting question.
What it is NOT is a statute or an on-point precedent which disqualifies Obama.
If you think the Vattel argument would be adopted by the USSC and then be retroactively applied to remove a sitting President, I think you are mistaken.
Your 2 citizen parents argument is not valid US law.
Then what, in your opinion, is valid US law?