Is what the young man did—undoing the magic and abandoning his wife until she is disciplined—correct, and what more should he do, knowing that he seeks refuge in Allah Almighty?

If there is a legally valid marriage contract between you and the woman, complete with all conditions, then she is your wife, and it is permissible for you to be in seclusion with her and enjoy her company. However, custom dictates that one does not consummate the marriage until after the wedding and the payment of the dowry. But if it is merely an engagement and a reading of the Fatiha, she is a stranger to you, and it is not permissible for you to be in seclusion with her.

Regarding the解除 of magic (sihr), it is not permissible to have it解除d by a charlatan who does not adhere to Islamic guidelines. One must be wary of anyone who requests a picture of the afflicted woman.

As for abandoning one's wife, if she is your wife and her condition has changed due to magic, then it is not permissible to abandon her; rather, you must help her overcome her condition.