Information in the possession of the petitioner necessary to prepare the adoption report shall be furnished with the petition for adoption by each petitioner for adoption or the petitioner’s attorney. The adoption services provider or other person concerned shall supply the court with such additional information in their possession as necessary to complete the certificate. The provision of such information shall be submitted to the court prior to the issuance of a final decree in the matter by the court, unless found by the court to be unavailable after diligent inquiry.