(1) If the department determines that due to employer error a member of plan 3 has suffered a loss of investment return, the employer shall pay the department for credit to the member's account the amount determined by the department as necessary to correct the error.
(2) If the department determines that due to departmental error a member of plan 3 has suffered a loss of investment return, the department shall credit to the member's account from the appropriate retirement system combined plan 2 and 3 fund the amount determined by the department as necessary to correct the error.