This part does not:
(1) modify the duty of an employer to provide a safe workplace for the employees of the employer;
(2) prohibit a person from engaging in constitutionally protected exercise of free speech, including non-threatening speech and speech involving labor disputes concerning organized labor;
(3) prohibit a person from engaging in an activity that is part of a labor dispute; or
(4) create an agency relationship between a nonprofit organization and a volunteer donating services to the nonprofit organization.