She states that when she was a child she was told that she had some Indian ancestry, and that proved to be true. What does the fact that she can't identify the individual who brought that DNA into her family line have to do with it? Some branches of my family tree I can trace - thanks to my late uncle - back to the 17th Century; with others, the information peters out after four or five generations. Does that mean I'm not descended from those people whom I can't name?
Family traditions have a way of being pretty on the mark. When I was a kid, I was told that my maternal grandfather's ancestor came to America by ship as an orphan, though who he was and when, exactly, it happened was unknown. Many years later, I discovered that my ancestor had, in fact, been brought to America from France after his Huguenot parents were killed in the persecutions of that sect under Louis XV.