"The gates of hell will not prevent against [the Church]". I do not rush to believe any reported apparition (we had one next door last year with a statue of Mary weeping). My faith does not depend on them. But on the other hand, I do not have a reason to disbelief an apparition that was studied for conformity with the General Revelation by my Church; in fact such disbelief would be a defect of faith.
Does not believing something, or being skeptical, even if your church says it is so affect your status in the RCC? As a Baptist, I question everything and measure it against what Scripture teaches.