Is a marriage that was conducted without a guardian (wali), and ruled upon by a judge, with doubts about its validity, considered zina (fornication), and is it permissible to renew the sharia contract now?

The marriage of a woman without a guardian (wali) is invalid according to the majority of scholars. If the marriage contract was concluded without a guardian, while believing in its invalidity, then repentance is obligatory. The validity of a contract without a guardian is a matter of scholarly disagreement; some scholars hold that the contract performed by a ruler (hakim) in the presence of the guardian is valid. If you wish to be cautious, renew the contract. This is permissible even if the woman is pregnant, as paternity will be ascribed to him. If the father refuses to renew the contract, her brother may perform the contract.