When any person runs or operates what is usually called a relief department for his employees, the members of which are required or permitted to pay dues, fees, money or other compensation, by whatever name called, to be entitled to the benefit thereof upon the death or injury of the employee, a member of such relief department, such person so running or operating such department shall pay to the person entitled thereto the amount it was agreed the employee, his heirs or other beneficiary under such contract, should receive from such relief department. The acceptance of such amount shall not operate to estop or in any way bar the right of such employee or his personal representative from recovering damages of such person for personal injury or death caused by negligence of such person, his servants or agents, as provided by law and any contract or agreement to the contrary or any receipt or release given in consideration of the payment of such sum, is and shall be null and void.