Is the marriage considered void if it was conducted in the Sunni Sharia Court in Lebanon with the mother as guardian, two witnesses, and the contract duly authenticated, given the father's absence due to his whereabouts being unknown, and the absence of paternal uncles or older brothers?

The guardian is a condition for the validity of marriage, and this is the view of the majority of jurists. The marriage that took place in court is valid. The father's guardianship over his daughter is not forfeited by his separation from her mother. He must treat her kindly, and he is not permitted to neglect her, for neglecting those one is responsible for is a grave sin. Efforts should be made to reconcile differences, as reconciliation is better than the status of fasting, prayer, and charity, and discord is the shaver (destroyer).