My recollection from looking at this at the time was that she didn't meet the requirements, but don't make the mistake of thinking these requirements applied to birth inside the United States. The maternal residency requirements only applied to a birth outside of the United States.
I believe it was the Naturalization act of 1952 that applies to Barack Obama.
I remember that the requirements changed. I detailed all that in FR posts at the time, but I don't have easy access to those posts now.
see my post 46
obamas mama was 18 at time of his birth did not have 5 years physical presence in usa