Should an engagement to a Sufi young man be annulled or continued, knowing that the mother fears people's talk?

Marrying a young man who has fallen into مكفرة heresies—such as offering worship at shrines or believing in immanence and union (ḥulūl wa-ittiḥād)—is not permissible. However, if he has fallen only into practical heresies—such as celebrating the Prophet's birthday or fasting on the middle of Sha'ban—then marriage to him is permissible, though someone else would be preferable.