Need an audiobook engineer!

My usual guy isn’t available, so I hired someone via Fiverr that supposedly worked with Grammy award winners, lives in Nashville, yadda yadda. Well! I really don’t like the sound of the book. It’s waay to sibilant and my voice too frayed. Not at all like my other audiobooks.
I have all the .wav files ready, I just need a new take/approach with the EQ.

Does anyone have any recommendations for audio engineering?

Thanks in advance,

Laurie