No, I'm saying that as that MediaMonkey didn't sync the files that it would sync the files to your PC additional to the ones you already have.

Only if that MediaMonkey synced the files to the device will it be able to sync back tag changes to the PC (not even the files would be synced as they already exist).

So are you saying all I need to do is sync the phone to my PC and it'll give me an option to override my computer's library file with the phone's? Do I need to delete the current library file first?

The primary problem is that you likely lost the MMW database. It contains the link between your MMA files and MMW files on the PC. Now that link is lost so MediaMonkey would sync the files back to the PC as new files.

I bought a new computer and before I had a chance to move all my files from my old computer it died. I was wondering if there is a way to preserve all my ratings and playlists (but in particular ratings are important to me) by syncing with my android? Or will my new computer override my old playlist and delete all the music? Are there certain files on my phone (I'm using the music monkey app with a micro SD card) that I could leverage to do this?