Sync music from iPod classic to iTunes? My Father's iPod (classic) has all of his music arranged and named perfectly.

However, his iTunes is not in sync with his iPod, as his computer hard drive was damaged, and all of his iTunes data lost. Because of this, we have not been able to back up the iPod, and if it is damaged, he will have to rename thousands of songs again.

Is there a way to sync the music from his iPod to his iTunes, or any other possible way to backup the iPod data?
Not officially.  Syncing is intended to go in one direction:  from iTunes to iPod.  

That said, there are some third-party apps that will permit this.

https://tunesgo.wondershare.com/music-transfer/transfer-music-from-ipod-touch-to-computer.html

Good discussion on Apple Support:
https://discussions.apple.com/docs/DOC-3991