Is a marriage contract valid if the suitor was married to the girl's maternal uncle instead of her adult brother due to the brother not possessing an ID card, given that the girl's father and paternal grandfather are deceased?

The woman's guardians who are valid to give her in marriage are her 'asabah—male relatives from the father's side—such as the father, grandfather, brothers, and paternal uncles. The maternal uncle is not a guardian for the woman in marriage. If the guardian—in this case, the brother—has explicitly or implicitly authorized the maternal uncle to solemnize the marriage, either by his presence or consent, then the marriage is valid and there is no need to repeat it.