Is it permissible to annul an engagement after the marriage contract (aqd al-qiran) due to the discovery of dyed grey hair on the head and a birthmark on the body that were not disclosed?

The majority of jurists hold that the defects necessitating disclosure during the engagement and annulment of the contract are those that prevent sexual intercourse or are repulsive and contagious diseases, such as leprosy and vitiligo. The presence of gray hair or a birthmark is not among what must be disclosed, but doing so is preferable to avoid conflict.

If the girl is righteous and religious, then complete the marriage with her. If you fear that this matter might cause future discord, then divorce her, for divorce before consummation is easier.

The meaning of "traditional engagement" is not clear. If it refers to the absence of the permissible looking (Nadhra Shar'iyya), then this is a mistake, as it is recommended. If it refers to going out and being alone with the fiancée, then it is not permissible in Islamic law before the marriage contract.