The existence of any agreement or agreements of the kind specified in section 43-158 shall not operate to impair the validity of any relinquishment or any decree of adoption entered by a court of the State of Nebraska. The violation of the terms of any agreement or agreements of the kind specified in section 43-158 shall not operate to impair the validity of any relinquishment or any decree of adoption entered by a court of competent jurisdiction. The parties to an exchange-of-information contract shall have the authority to bring suit in a court of competent jurisdiction for the enforcement of any agreement entered into pursuant to section 43-158.