(1) The liability of a carrier or fund regarding a claim under this act shall be determined by the hearing referee or worker’s compensation magistrate, as applicable, at the time of the award of benefits.

    (2) If a carrier or fund originally determined to be liable pursuant to subsection (1) is subsequently determined to not be liable or not to the same extent as originally determined, that carrier or fund shall be reimbursed by the liable party or parties with interest at 12% per annum.