“My children, I have come to tell you that this is not a real apparition.”

No, our Lady is not appearing on the window of a hospital in Springfield, Mass.
Allow me to translate: when the church spokesman says that the Church is “very, very cautious and careful”, that means: “No. No Flipping Way. This is nuts.” Unfortunately, church spokesman are polite to a fault, and it gets in the way in cases like this.
By the way, Boston-area faithful may remember the similar case at a hospital in Milton in 2003. There the “image” was traced to some chemicals that penetrated a leaking double-paned window.