iPhone won't sync with Apple Music app on Catalina using Finder

Hi, I'm having a tough time getting my iPhone 11 Pro to sync with my music library post move to Catalina. I'm aware the sync happens in the Finder now. My music is stored on a NAS drive as it has always been. Sync worked just fine with iTunes. Now with Music, my iPhone will not sync to Music any longer. I'm certain the music library points to the NAS folder.

In the Music on my Mac, when I select my iPhone, I can see all of the Music which appears to be on the phone. However, when I go to the phone, most of the music isn't there. I tried deleting all music from my phone through Settings->Music->Downloaded Music, the delete all songs. Now it shows Zero KB, but when I open the music all on my phone, some music is still there. I'm not syncing anything to iCloud, I don't think unless something at some point happened automatically. Sync Library on the iPhone is disabled. On the Mac, in Music, Preferences->General->Library is unchecked and grayed out, so it doesn't look like anything is syncing across the cloud.

I have no idea how to fix this. I've tried multiple times in the Mac Music app unchecking and rechecking the sync music onto my iPhone, and nothing appears to happen. The other strange thing is Mac Music displays 42.96 GB available on my phone whereas the phone shows about 194 GB free.

In case it matters, I'm syncing using the USB-C to lightening cable that came with my iPhone Pro 11, not trying to do it over WiFi. Finder recognizes the phone without any problems and I've told the phone to trust the Mac.