In the absence of fraud or mistake in mathematical calculation, the findings of fact in and the decision of the Director upon the merits of any claim presented under or authorized by the internal revenue laws and the allowance or nonallowance by the Director of interest on any credit or refund under the internal revenue laws shall not, except as provided in subchapters III and IV of chapter 47 (relating to judicial review), be subject to review by any other administrative or accounting officer, employee, or agent of the government of the United States Virgin Islands.