If the marriage was legal, this would apply. Neither British law nor U.S. law recognizes bigamous marriages as legal, and thus the children of such marriages are as if born out of wedlock.
So the only way he could possibly be born anywhere but this country and still be a citizen is if he was born out of wedlock, which he clearly states he was not.
Who clearly states this?? Obama wrote in one of his books that he had doubts about his parents' marriage.
You’re saying Obama wasn’t sure if his parents were actually married? Do you have a quote from him about this?