"Willful nondisclosure" occurs when:

(1) An employee omits or fails to disclose information;

(2) The employee either knew or should have known that the information should have been provided;

(3) The information concerned a fact that was material to the employee's rights and responsibilities under Title 50A RCW; and

(4) The employee omitted or did not disclose the information with the intent that the department would take action on other information the employee did provide.