The last time I checked, the House of Representatives was just half of one branch of government. It cannot make laws without the Senate and President concurring. Did this definition make it into a law? Was this law superseded by future court cases and newer laws?
You’re right that Congress cannot pass laws that establish with authority and force of law what the Constitution means.
However, courts can and do refer to statements made in Congress, and to laws and resolutions passed by Congress, as an aid to help them determine what Congress meant when it passed laws and drafted Constitutional amendments. Of course, that’s only done when the Congressmen whose words are used for that purpose at least participated in the debates on the laws or Constitutional amendments whose meaning the court is trying to ascertain.
In the case of the Congressional statements quoted above concerning the meaning of “natural born citizen,” the Congress where those statements were made did in fact include those who not only debated the 14th Amendment, but in fact wrote and championed it. So courts would definitely give it some weight for the purpose of understanding intent.