First: "By their fruits" is not the first test of the authenticity of an alleged supernatural event. God is perfectly able to bring bad from good, especially in someone who is truly inclined to charity and humility. The bad is not to be sought out for this (or any other reason), but if a person can draw good from it, he turns the devil's weapon against him.
Second: Medjugorje is (as you know) not without controversy and scarcely to be invoked as a guide to another controversy.
Third: one can believe (as I do) that there is an active and benevolent divine presence while remaining skeptical about some purported manifestations of it.
Fourth: Nearly every alleged revelation has its supporters, even among the clergy, even after it has received formal disapproval.
Fifth: The book was placed on the Index in an order signed by Pope John XXIII. The Index has not lost its moral force.
I can only second Fr. Pacwa's advice and leave it at that:
Fr. Mitch Pacwa wrote:
When Catholics insist on reading "Poem," despite Church condemnation, I make these requests: First, read three hours of Scripture for every one hour spent in the "Poem." The Church guarantees that the Bible is God's Word, inspired by the Holy Spirit. The Church has judged the "Poem" to be a poorly done human work. Second, read solid Catholic theology books in addition to Scripture. G.K. Chesterton, Frank Sheed, Archbishop Sheen's "Life of Christ" and many other works are excellent starts. Third, maintain a strong prayer life, drawing closer to Christ Jesus, Our Lord, at Mass and at eucharistic adoration, and to our Blessed Mother Mary, especially in the Rosary.
If sheep insist on bad pasturage, at least let them take antidotes.