It is really a silly argument. There is a court case from about a hundred years ago where a Pennsylvania Supreme Court judge decided that voting, as mentioned in the state constitution, meant to vote in person. That became an issue when Pennsylvania wanted to establish absentee voting and they decided to put absentee voting into the Constitution. There was a lawsuit over whether an absentee voting law would be constitutional based on that old ruling about what "voting" means in the constitution, but they ended up just working around it.
If I recall, that ages old opinion was not actually part of a court opinion but a concurrence by one judge. Not exactly a precedent, but it still carries some legal weight.
If I recall, the decision by that judge was based on concerns about voting that no longer apply.
If I recall (I keep saying that) this court case was tossed out on laches and the court did not consider the issue.
If a case was brought now or if it had been brought early last year, the court could consider that argument. The court would probably dismiss the old decision as no longer applicable or relevant. But maybe not. But probably.
The court could not even consider it because it wasn't raised until after the election. Similarly, Congress should not consider it because it wasn't raised until after the election.
There is no reason that Congress should rule on an interpretation of a state constitution when under principles of law a state supreme court cannot rule on an interpretation of a state constitution. The same rules of law apply. Although they actually apply much less to Congress than they do to the court. The idea that Congress should decide when the state court cannot is simply a perversion of law.
