; and (2)(A) the opinion of the head of the Federal agency as to whether a violation of section 1341(a), 1342, or 1517(a) of title 31, United States Code, as applicable, has occurred; and (B)(i) if it is the opinion of the head of the Federal agency under subparagraph (A) that a violation has occurred, an explanation as to why the violation was not discovered and reported by the head of the Federal agency prior to the date of the notification by the Comptroller General of the United States