Look, forlorn, the "private judgment" thing is about private interpretation of the depositum fidei. Or, for protestants, about private interpretation of Scripture.
As Catholics, we have a Magisterium who is competent to do the interpretation. But then, after the Magisterium has done the interpretation, then interpretation is over and dogma has begun. With dogma, there is no more interpretation. To claim that dogma needs interpretation again, is nonsensical because it would lead to an infinite regress.