So you and the Catholic Church think that The Dogma of the Assumption of Mary must be believed in order to be saved? Yet that was not made a dogma until 1950! So no one was saved until 1950 per the Catholic Church? The apostles didn't even teach what must be believed (according to the Catholic Church) to be saved? That's an astounding belief! To think that for hundreds of years no one was saved.
Even the Catholic Church says it was not believed for hundreds of years. It says:
"The doctrine of the Assumption was one that developed over time. It was not something new but rather the logical result of what was already known (Mary’s Immaculate Conception). Since corruption in the grave was the result of sin (Genesis 2:17) it was only logical to think that someone without sin would not suffer such a fate." [http://www.staycatholic.com/ecf_assumption.htm]
A "logical result"? "it was only logical"? Here's another statement.
"If therefore it might come to pass by the power of your grace, it has appeared right to us your servants that, as you, having overcome death, do reign in glory, so you should raise up the body of your Mother and take her with you, rejoicing, into heaven. Then said the Savior [Jesus]: "Be it done according to your will" (The Passing of the Virgin 16:2-17 [A.D. 300]).
"it has appeared right to us"? Not until 300AD and then only because "it has appeared right to us"? No teaching by the apostles. No mention of it untill 300AD! But then because "it has appeared right to us"? Now it's a dogma that people have to believe to be saved?
So tell me, who was saved prior to 1950? Or was it 300AD? When did people begin to be saved?
Maybe all those people prior to 1950 are still in Purgatory? ;o)
Obviously, no one can be blamed for doubting a doctrine not yet infallibly proclaimed. Even now, the Church asks that the dogmas be studied and a serious effort be made understanding them, but not blind unthinking obedience. It is a flippant negation of the Church teaching, no matter how recent, that is sinful and may preclude entry into Heaven.