The cults succeed quite well in turning folks away from Christ by seductively dismissing, minimizing, directing away from or trashing HIS DEITY.
They can quite skillfully use truth, half-truths and bits of truth to accomplish that.
Fatima succeeded in the priority goal of the enemy on such scores by glorifying the Ashteroth-Mary-Goddess caricature INSTEAD OF JESUS THE CHRIST.
As Scripture makes very clear, HOLY SPIRIT AND WHATEVER HOLY SPIRIT DOES GLORIFIES CHRIST.
So you have no evidence to prove the Fatima apparitions daemonic, aside from the fact that the apparitions were Marian.