Congrats on your audiobook. I can see that you did not do the narrative yourself. I am finding that my voice is not as good as it used to be, so I would use a better voice, myself.
People have asked if my books are audiobooks. I really should have gone ahead and tried to get them published that way. But I keep dragging my feet. I have found that my computers and my Dragon system can actually read back my dictation in my voice. Or, I can have my work read by the computer in several voices. What little I have stopped to listen to, has been quite good. Providing pauses and other nuances that a good reader would provide. That is one reason I haven't gone ahead with creating an audiobook. If I have the book online, computers can read it back. No humans required AI is getting that good!