Parents obviously means a mother and a father.
People can think that NBC means something other than what originally intended. Your choice.
A natural born citizen is born of citizen parents on American soil. No more, no less. That was the decision of the Founders and when the 1790 amendment was crafted in a flawed form James Madison and several other Founders insisted that the Statute be repealed not amended to guard against any possibility of foreign born children of citizens being deemed eligible to become president.
An excellent discussion of these points here
The State Department is also very clear as I have discussed up thread. Citizenship obtained by statute is the citizenship of the 14th Amendment. People have agendas and are paid to have opinions but the Constitution, evidence of Founder's intent, early Congressional Actions & contemporaneous court cases tells a very consistent tale.