Any vehicle used in connection with any commercial vehicle safety relocation service must carry in the power unit of the vehicle a certified copy of the currently effective safety relocator‘s registration certificate. Copies may be photographed, photocopied, or reproduced or printed by any other legible and durable process. Any person guilty of not causing to be displayed a copy of the safety relocator’s registration certificate may in any hearing concerning the violation be excused from the payment of the penalty hereinafter provided upon a showing that the registration certificate was issued by the Commission, but was subsequently lost or destroyed.