Wow, this is just going over your head, isn't it.
Reynolds was a question about 1st Amendment protections with respect to the question of plural marriage - or any other illegal act. The central legal holding in Reynolds was that the 1st Amendment was NOT an allowable defense for committing a crime. That's it. And, that has NOTHING to do with MA v. HHS.
In this District Court opinion, the judge holds that MA v. HHS is unconstitutional because of the 10th Amendment.
Reynolds and MA v. HHS are decided along ENTIRELY DIFFERENT legal principles. Reynolds has NOTHING to do with MA. v. HHS. One is a 1st Amendment case, and the other is a 10th Amendment case.
And this is why the ruling will be overturned. DOMA has no 10th Amendment implications. DOMA does 2 things:
1.) It provides that states are not obligated to recognize same-sex marriages performed in other jurisdictions. While this may be seen as a violation of the Full Faith and Credit clause, it is not a 10th Amendment issue.
2.) DOMA defines marriage as the union of a man and a woman, only "In determining the meaning of any Act of Congress, or of any ruling, regulation, or interpretation of the various administrative bureaus and agencies of the United States". In other words, DOMA defines what the word "marriage" means for the federal government and in applying federal laws and regulations. It does not interfere with the ability of states to define marriage in whatever manner they choose. Once again, no 10th Amendment issue is raised.
Then why does the federal government ban bigamy? The 10th cannot abrogate the common law definition of marriage. It’s never been a state responsibilty to define marriage for itself.
If you had read Reynolds all the way through, they address your argument.