My boss hired Thelma French after I informed him of my managers misconduct, which included yelling, refusing to pay for a medical certificate even though it was requested after one day off and I was under quota, humiliating me and threatening me with a performance review because I refused to "take a cold and flu tablet and come into work" with a contagious virus (we worked in a clinical environment I might add).
She was presented to me as a mediator, even though my manager was not included in the meeting she set up. She failed to inform me and my HR consultant of an outline of the meeting in advance, which turned out to be a warped and manipulated performance review, essentially accusing me of provoking these responses. A lot of what they accused me of either conflicted with my previous performance review or my boss admitted was not an issue. The subject of misconduct was avoided and eventually, In frustration my boss finally admitted it happened but was "not a big deal."
As my HR person prepared to end the meeting as It was obviously not getting anywhere, Thelma hurriedly called for a "break" and upon return, changed direction entirely.
After the meeting whereupon they agreed to talk to my manager, Thelma continued to support my manager with emails such as "you are exactly what (bosses name) needs" and others of such thinking while she failed to even touch base with me. My manager was allowed to ignore my very existence for two weeks, and after seeing that I was going to get no help from Thelma I quit. Because I was nineteen and naive, I let her help my boss to walk all over me.
My advice: if you are going to hire Thelma French or associates, make sure YOU understand the protocols and protect yourself.
If your boss has hired her, hire your own HR consultant. She is entirely on the side of the money, not the solution.