then the operator is liable to the United States for repayment to the fund of the amount of such benefits the payment of which is properly attributed to him plus interest thereon. No operator or representative of operators may bring any proceeding, or intervene in any proceeding, held for the purpose of determining claims for benefits to be paid by the fund, except that nothing in this section shall affect the rights, duties, or liabilities of any operator in proceedings under section
932 or section
933 of this title. In a case where no operator responsibility is assigned pursuant to sections
932 and
933 of this title, a determination by the Secretary that the fund is liable for the payment of benefits shall be final.