I think you unintentionally committed a gaffe here. There were Protestant ministers invited to observe Vatican Two. But, despite claims made by those wandering the fever swamps of schism, they were not responsible for the normative Mass. The normative Mass or the Mass of Paul VI is as Catholic as any Mass celebrated by priests prior to Vatican Two.
If Protestants really were responsible for our normative Mass, why don't any Protestant Churches celebrate the mass of Paul VI?
I think Catholics forget, or may have never even heard, that Protestants were invited to observe the Council of Trent. Not only that, they were invited to debate any topic, Doctrine etc they chose to debate. Just because a Protestant is invited to observe an Infallible Ecumenical Council doesn't mean it's results are suspect.