What is the ruling on "M" marrying "S" after "S" sought a Khul' divorce from her second husband, who had married her " عرفيًا" (unofficially/customarily) and did not divorce her, knowing that "S" performed the Khul' herself in front of his colleagues at work? And are there any special rulings that apply to this marriage in this situation, especially after three years have passed since their marriage?

It must be clarified whether the divorce from the first husband occurred in a Sharia (definition)-compliant manner, by the husband's choice or under duress, because the validity of subsequent marriages depends on this. What happened between the woman and the second man is adultery, which necessitates repentance. Furthermore, the validity of her marriage to the second man and the divorce from him are unclear, and khul' (divorce at the wife's instance) cannot occur without the husband's consent.