; preliminary order If the Secretary concludes that there is reasonable cause to believe that a violation of subsection (a)(1) has occurred, the Secretary shall accompany the Secretary’s findings with a preliminary order providing the relief prescribed by paragraph (3)(B). (C) Right of parties to appeal Not later than 30 days after the date of notification of findings under this paragraph, the employer or employers alleged to have committed the violation or the complainant may file objections to the findings or preliminary order, or both, including the dismissal of the complaint, in whole or in part, and request a hearing on the record before an administrative law judge of the Department of Labor. Any such hearing shall be conducted expeditiously. If a hearing is not requested in such 30-day period, the preliminary order shall be deemed a final order that is not subject to judicial review. The filing of such objections shall not operate to stay any reinstatement remedy contained in the preliminary order issued under subparagraph (B). The Secretary of Labor is authorized to enforce preliminary reinstatement orders in the United States district court for the district in which the violation was found to occur, or in the United States district court for the District of Columbia. (D) Dismissal of complaint (i) Standard for complainant The Secretary shall dismiss a complaint filed under this subsection and shall not conduct an investigation otherwise required under subparagraph (A) unless the complainant makes a prima facie showing that any behavior described in subparagraphs (A) through (G) of subsection (a)(1) was a contributing factor in the adverse action alleged in the complaint. (ii) Standard for employer Notwithstanding a finding by the Secretary that the complainant has made the showing required under clause (i), no investigation otherwise required under subparagraph (A) shall be conducted if the employer demonstrates, by clear and convincing evidence, that the employer would have taken the same adverse action