Every policy of insurance and every guarantee contract covering the liability of an employer for compensation shall cover the entire liability of such employer to his or her employees covered by such policy or contract and also shall contain a provision setting forth the right of the employees to enforce, in their own names, the liability of the insurance carrier in whole or in part for the payment of such compensation, either by filing a separate claim at any time or by making at any time the insurance carrier a party to the original claim. However, the payment in whole or in part of such compensation by either the employer or the insurance carrier shall, to the extent thereof, be a bar to the recovery against the other of the amount so paid.