How to contact DM anonymously

There is some major issues going on in my store that need to be addressed. It involves the store manager herself and I’m tired of witnessing the bullying. Her and another partner flat out talk shit on the floor making it obvious. Even going as far as calling people idiots. I’ve asked a simple question and got “use your brain!” Just a lot of belittling going on without any consequences. She even said to be open and express when something hurts your feelings. But when partners try to do that she becomes extremely defensive & will not take accountability.

How would I go about contacting the DM ANONYMOUSLY? I do not want her to know who I am because I guarantee work would become my personal hell.