Provides that, if the department has made a medical coverage decision denying the request of a worker entitled to benefits under Title 51 RCW for coverage of a particular medical or surgical treatment under RCW 51.36.010 and the worker subsequently receives the medical or surgical treatment at personal expense, by using private insurance, or by using any other means, the department or self-insurer, as the case may be, shall reimburse the payor for the cost of the medical or surgical treatment, shall pay the treating provider any remaining balance unpaid by the worker, and shall consider the treatment proper and necessary treatment for the worker under RCW 51.36.010, if the worker has provided: (1) Adequate documentation of the medical or surgical treatment performed for a condition accepted by the department or self-insurer, as the case may be; and

(2) Medical evidence that shows that his or her condition has reasonably improved after the medical or surgical treatment is completed.