How to restore missing iTunes Playlist Folders?

I have created hundreds of itunes playlists on my pc. I put them into folders that I create in Itunes. One of them which had probably 200 individual playlists in it has suddenly vanished. NONE of my songs/mp3s has vanished...just the 1 folder containing my dj playlists. All other playlist folders are still there. I've never backed-up/synched my library to itunes/the cloud. I have backed up as recently as July to an external hard drive. I've looked in all existing folders cause sometimes a folder can be moved into another. But nope. Not there. I can find a "Itunes Library.xml" file on my external drive should I try importing that to the library? I also tried importing a iTunes Library.itl file but itunes didn't recognize it as a valid file.

Is there anyway to restore this missing folder?

Using Itunes 12.13.2.3 on a windows 10PC

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