Downloaded files from Apple Music

Edit: I've fixed it, see solution and original question below.

Solution: I had taken a backup of my entire computer before reloading, I was able to copy the library file back over to my computer, then hold option, click on music, click choose library, and chose the original library file. All is well.

Original question:

I have quite the offline collection that I downloaded from Apple Music through my subscription. The intent is that, I'm generally on low speed internet connections and I want to be able to listen to music without having to stream it all. I recently had to reload my laptop and I have all of these downloaded files, but Music is showing them as back to streaming. Any way to re-link these files up to Music so that it plays the local version and not the stream?

Same iCloud user, same subscription, **** even same laptop, just fresh install.

I've tried the obvious of both CMD+O and drag/drop into Music to no avail.