The short answer is, no one. Parliamentary procedure is NOT subject to Judicial review, or least it never has been in the first 235+ years of the country.
The Judiciary isn't going to insert itself into this matter, I'd wager. Because of the Separation of Powers and Art. I, Sec. 5, the Judiciary isn't going to peak it's nose under the Congressional tent. Which means, we are in uncharted water here. The Democrats are turning the Constitution on its head, and there really isn't any way to undo it, other than at the ballot box.
This is where NOT having a fair and honest media is really going to hurt. If it were the Republicans making a mockery of the legislative process like the Democrats are now, the MSM would be going into convulsions. It literally would be the biggest story since Watergate. As it stands, it's clear that most of the traditional media is going to look the other way as SanFran Nan burns the Constitution.
You are quite right that NORMALLY the courts do not interfere in the procedural rules of any legislature. I say that in my column, and if I had had more space than the usual 750 words, I would have cited a Supreme Court case where it refused to look into the ratification rules of the Ohio legislature concerning the proposed Equal Rights Amendment.
However, there have been exceptions to that rule. The Powell case, which I discuss in detail, is such an exception. So it has been done. So it can be done again.
John / Billybob