You can’t pass a law with a “ not reviewable by SCOTUS” provision.
That’s what they do.
The REAL answer was a Constitutional amendment that would have defined marriage when the support was there for it. THATS why the spin at the time was it “ wasn’t necessary DOMA was all that was needed.”
Art III, Sect 2: In all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party, the supreme Court shall have original Jurisdiction. In all the other Cases before mentioned, the supreme Court shall have appellate Jurisdiction, both as to Law and Fact, with such Exceptions, and under such Regulations as the Congress shall make.