It’s true, not many trust [or believe in] apparitions, and yet.... there have been battles won by those who have recited the rosary...
Battle of Lepanto
On October 7, 1571, a great victory over the mighty Turkish fleet was won by Catholic naval forces primarily from Spain, Venice, and Genoa under the command of Don Juan of Austria. It was the last battle at sea between “oared” ships, which featured the most powerful navy in the world, a Moslem force with between 12,000 to 15,000 Christian slaves as rowers. The patchwork team of Catholic ships was powered by the Holy Rosary of the Blessed Virgin Mary.
https://www.ewtn.com/library/mary/olislam.htm
With all due respect, I believe Mary was no more righteous than we are and that the elevation of her by Catholics is very sinful. God may or may not answer the Bishop’s prayers, but it won’t be because of his idolizing and praying to Mary. If he honors it, it will be in spite of his sinful adoration of Mary.