I'm using someone else's phone so no one will know who it is. I need to report an employer for sexual harassment, verbal abuse, and basically treating his employees like slaves. Who can I contact?

I would start first with HR. Then with your local police. I work for DHS and if the 2 above doesn't work let me know.

Division of Civil Rights . They are very helpful. Don’t know where you are located , but google this place to the state you live in and go from there