I fully understand what you are saying. And I agree that your working definition of the difference between "dogmatic" and "pastoral" is a good one. I also agree that it appears that most legitimate theologians seem to generally grasp the same meaning of these two words.
Ok, TKGS.
I agree the enemies of the Church have tried, and to a great degree, succeeded, in manipulating doctrine and confusing Catholics who wish to remain faithful. The question is to what extent, and also, what can be done about it.
Personally, I think the best thing for Catholics who know their faith to do is simply for practical purposes to ignore the Council, and to believe all the dogmas the Church has ever defined. That's the approach of the FSSP and other Indult groups, I know sedes have a different point of view.
I don't think there has been any formal definition as to what "pastoral" means.
Regarding what you asked, Pope Benedict XVI, when he was Cardinal Ratzinger, with Pope John Paul II's agreement said,
"The Second Vatican Council has not been treated as a part of the entire living Tradition of the Church, but as an end of Tradition, a new start from zero. The truth is that this particular council defined no dogma at all, and deliberately chose to remain on a modest level, as a merely pastoral council; and yet many treat it as though it had made itself into a sort of superdogma which takes away the importance of all the rest"
SJB, while I agree with Archbishop Lefebvre's concerns, yet the necessity of the Church, the fact that hell exists and souls go there, are explicitly reaffirmed in the Council.
"In explicit terms He Himself affirmed the necessity of faith and baptism(124) and thereby affirmed also the necessity of the Church, for through baptism as through a door men enter the Church. Whosoever, therefore, knowing that the Catholic Church was made necessary by Christ, would refuse to enter or to remain in it, could not be saved.
...
But often men, deceived by the Evil One, have become vain in their reasonings and have exchanged the truth of God for a lie, serving the creature rather than the Creator.(129) Or some there are who, living and dying in this world without God, are exposed to final despair. Wherefore to promote the glory of God and procure the salvation of all of these, and mindful of the command of the Lord, "Preach the Gospel to every creature",(130) the Church fosters the missions with care and attention."
I agree with Archbishop Lefebvre, but even a near-complete apostasy or confusion of faith among clerics and prelates, if you'll excuse the expression, poses no "dogmatic" problem, only a "pastoral" one. What I mean is, there's no guarantee something like that can't take place, but I do think there is a guarantee the universal episcopate assembled in Council even without a Pope, as you believe, cannot teach formal heresy.
Also, such a loss of faith happened once before during the Arian crisis, the majority of Bishops became heretics. Heretics will always find something to appeal to. If after Nicaea, Arianism could still pretend itself feasible, then heretics can always find an excuse. I don't deny they pretended the Council did away with hell, with missions, with morality, with the need for conversion from false religions etc, so the Council gave them a pretense, at least, so it has in that sense a "pastoral" failure.