If an employee files a complaint with the department alleging that their employer failed to pay to the employee all tips and gratuities due to the employee under RCW
49.46.020, or all service charges due to the employee under RCW
49.46.020 and
49.46.160, the department will investigate the complaint. The department will investigate the complaint pursuant to the procedures outlined in the Wage Payment Act, RCW
49.48.082 through
49.48.087.