There are two scenarios where it appears the consideration of the validity of a constitutional amendment would previously require a ruling that it is unconstitutional.
Scenario 1: the amendment is kinda similar to the eleventh amendment, and it prevents the judicial system from challenging the constitutionality of an amendment once it's recognized as part of the Constitution by the Archivist of the United States.
Let's say the Congress adopts this amendment, leaving it in instance before the states, but before any state has taken action on the amendment the Archivist registers it as part of the Constitution. Let's say a suit is filed by some entity having standing on the matter (somehow): the amendment is invalid, because the process of adopting it was illegal, but to even consider its possible invalidity, you have to contradict the amendment's provisions, which means pre-judging it as invalid. Which is kind of a paradox.
Scenario 2: the amendment deprives three particular states (Maine, Vermont and Illinois for example) of suffrage in the Senate, and it also prevents the judicial system from taking into account the contents of an amendment when challenging its validity. Let's also assume these two points somehow are written in such a way that it's impossible to separate one from the other without entirely changing the amendment.
This time, the Archivist does nothing as absurd as in the first case, but he files the amendment as part of the Constitution when 3/4th of the states (not including Maine, Vermont or Illinois) have ratified it. Same issue: the content of the amendment makes it invalid due to the last clause of Art. 5 of the Constitution, which forbids amendments preventing equal representation of states in the senate without their consent, but recognizing that implies the same paradox as in scenario 1.
In these scenarios, what could or would the judicial system do? Would it have been possible for the amendment to be blocked between the time it is proposed and the time it's ratified (or considered as such by the Archivist in s.1), or would that be contrary to legislative immunity?