Help to Remove Ghost Audiobooks in Finder iPhone Sync

I am using a 2019 iMac running 13.6.6 "Ventura" with an iPhone 16 running iOS 18.6. I do not use iCloud in any way. I sync files between by iMac and iPhone using the Finder and a USB cable. All of my audiobooks are rips of CDs I own (or A2D conversions of cassette tapes I own).

There are about 17 nonexistent ("ghost") audiobooks "stuck" in the Finder Audiobook sync tab for my iPhone, and I can't find any way to delete/remove them.

To simplify troubleshooting, I have deleted all content from the Books app on my Mac. There are no audiobooks at all (nor ebooks, for that matter). Books shows this.

Further, I've verified that the directory where Books stores audiobook files is completely empty. No audiobooks, no plists, no nothin':

~/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks/Books/Audiobooks/

There are also no audiobooks on my iPhone. So, as far as I can tell, I am currently "audiobook-less". You may safely assume I've already taken the basic steps of restarting the app, my iMac, the iPhone, etc.

However, when I attach my iPhone to my iMac, select it, select the Audiobooks tab, and choose the option to Sync: All audiobooks, I see a list of about 17 nonexistent audiobooks. Here's a screenshot showing a partial list.

If I proceed with the actual sync by clicking the Sync button, I get dozens of error messages saying for each book/chapter that "The file was not found."

I've tried various iterations of syncing and un-syncing my phone. I've played with the option to sync Selected audiobooks, and while choosing this option and unselected all of the ghost audiobooks stops the error, it doesn't solve the problem of actually removing them. I can find no way to delete them from the Finder iPhone sync Audiobooks page. I've hunted around in ~/Library/Caches and deleted any folder with "books" or "audiobooks" or "iTunes" in the name (actually didn't delete them, just appended a ".Deleteme" to the file name). I've reviewed this support article, and this other article, and wasn't able to solve it. I no longer have most of these audiobooks, so it isn't possible to "put them back", and even if I did, I have no way of knowing where each of these ghosted entries is expecting to find the source audiobook files: the error messages don't say.

Clearly something is cached somewhere and I can't find where to clear it, nor how to clear it. I'm frankly surprised that there isn't a Refresh button on the page to deal with this exact problem, and Apple's documentation is of no help. Any help from the community would be appreciated. Thank you!