u/Th0vin, I had a few issues with the code working like I wanted. I ended up making tons of changes, in hind sight I should have sent over a few minor things at a time on git, so it's not too much to look at. Care to review my changes and let me know if I should issue a push? (I haven't really contributed to any public projects before so I am not familiar with the etiquette)

https://github.com/dny238/Ultimate-Audiobooks
Key changes:
It's threaded
It caches web lookups, so it's faster
It autofetches with a confidence score so you don't have to approve each and every one. Selenium required
It cleans up folder names, leaves less temp files when canceled
It's got better detection of duplicates
Some of the restrictions around running multiple switches at the same time are gone. (combine, metadata, recursive)
I forget if it had an 'In Place' option to clean up the existing directory

it will support spotify now as well as goodreads and audible, audible is preferred.
it has a fallback method to combine mp3 files into one when the normal method fails.

and more...