Whether or not Harris is qualified is an academic question. She will not be removed from any ballot on that basis, and if she wins, Congress will seat her.
We can see from Obama and cubanadian Cruz that nobody in the political system is serious about the natural born citizen clause of the constitution. Should be quelle surprise, as they aren't serious about various other clauses either, like commerce clause; and certain rights have been literally hallucinated into existence (abortion, homo marriage) while fundamental rights like RKBA get substantially diluted.