Incredulity is not a refutation.
Are you denying the scripture says God changed the divine plan at her prompting?
Answer yea or nay, and we can proceed.
Do you think that God was not aware of the wedding at Cana? Do you think He actually was persuaded to change some "divine plan" for revealing the divinity of Jesus, just because Mary asked Him to perform miracle at a wedding? If so, you once again fail to reckon with the true nature of God.