What is the ruling on a marriage contract concluded without the presence of two witnesses, where the ma'dhun (registrar) suffices for that, and does this contradict the Hadith: "There is no marriage except with a guardian and two just witnesses"?

What the marriage officiant stated about him taking the place of two witnesses in the marriage is not legally sound, because the testimony of two upright witnesses is a pillar of marriage. The majority of scholars stipulate that two upright witnesses must witness the marriage contract, while the Malikis stipulated witnessing upon consummation if it was not done at the time of the contract. It is not permissible for the officiant to be one of the two witnesses in the marriage. If the contract was concluded with the officiant's testimony alone according to the Malikis, it is valid if two upright witnesses testify to it before consummation. If consummation occurs without witnessing, the contract is annulled with an irrevocable divorce, and it must be renewed with its legal pillars.