It shall be unlawful for any employer to directly or indirectly demand or collect from any of his or her workers any sum of money whatsoever for or on account of medical, surgical, hospital, or other treatment or transportation of injured workers, other than as specified in RCW
51.16.140, and any employer who directly or indirectly violates the foregoing provisions of this section shall be liable to the state for the benefit of the medical aid fund in ten times the amount so demanded or collected, and such employer and every officer, agent, or servant of such employer knowingly participating therein shall also be guilty of a misdemeanor.