Lightroom Folders showing "0" images, can't find solution

Lightroom CC -desktop. Windows 10 PC.

In library mode, nearly all of the folders in one of my external drives show 0 images, but the images are all there on the external drive. I've read the other forum posts on the situation and they don't seem to come up with any solutions, except reinstall an old catalog, which isn't much of a solution.

I'm guessing one of two things led to this problem. 1. After working for awhile, then taking a break and putting computer to hibernate, I couldn't get my physical or onscreen keyboard to work to log back in, so I restarted computer with a couple clicks of the mouse with Lightroom and another one or two programs running behind the log-in screen.

Or, 2. Most of my images on my external drives are in different dated folders in a folder labeled "photos". So every external drive has a "Photos" folder, but there are never any actual photos in it, only in the different date/event labeled folders inside the "Photos" folder. I transferred 2 images from one external hard drive to the "Photos" folder, but not another event specific folder, on the external drive I'm having problems with. So there are now two images in the "Photos" folder.

So in the catalog panel on the left, there is now a "Photos" folder in external drive "X", but most of the older folders with images in them previously, are listed above the "Photos" folder, and show no images, though they have thousands of images in them and I've been working on them for months in lightroom. If I try to re-import the images, the images show up, but at note says they've already been imported, so aren't selectable to import. I hoped right-clicking on the "Photos" folder in the external drive listing in the catalog panel and selecting synchronize folder, would solve the problem. It hasn't. I have gotten the message that others have posted:  "An internal error has occurred : Database "C:users, etc lightroom-catalog, etc... "UNIQUE constraint failed: AgLibraryFolder.pathFromRoot  Statement: UPDATE AgLibraryFolder SET rootFolder = ?,pathFromRoot =  ? WHERE".

Now, a few images are showing up, but just a handful that have recently been exported to newly created folders. Any thoughts or help is greatly appreciated. This project has been the most agonizing, frustrating I've ever experienced. The drive has about 850GB's so we're talking about 30,000+ photos. Sadly it looks like I hadn't backed up the catalog for six weeks, when I've done the most work on 500 most important photos on the drive. The funny thing is, it appears the metadata is up to date on the recently exported .jpg's and .tif's. I sure hope that is the case on my raw files, if I can restore them.

Thanks!!