The Church allows, but does not require or speak infallibly about such apparitions. Many Catholics do believe in Fatima and the promises about the scapular, (which I believe was given in another apparition). Many are skeptical. Both are allowed.
PLEASE UNDERSTAND THAT CATHOLICS ARE REQUIRED TO BELIEVE THE TEACHINGS OF THE CHURCH AS TAUGHT BY SOME COUNCILS AND RATIFIED BY THE POPE. THEY ALSO HAVE TO BELIEVE IN TWO INFALLIBLE STATEMENTS BY THE POPE ABOUT MARY.
If the apparition is the same Mary of the Bible and the one that catholics have written who knows how many books, prayers, songs about and named too many buildings after then what's the problem??
I think it's because the false promise contradicts Scripture.
Catholicism likes to have it both ways on mary. The "positive" stuff they believe and share with everyone....the false stuff like this they run from.
Too bad ROME wasn't so forgiving about what folks could BELIEVE bad in the day!