Because it was through his intercession that she was healed.
And how can you be so sure of this?
You know this for a fact?
If, and that is stretching for me, he interceeded, all he did was ask. God performed the miracle. Not the pope. I don't understand how the deceased pope can be credited with a miracle that he isn't capable of performing alive or dead no more than you or me. Only God performs miracles.