Reattach previews / smart previews with corrupt catalog in Lightroom 5?

Hi there,

  About a month ago I got a notification that my lightroom catalog was corrupt. This was the first time it happened after 10+ years of using Lightroom. Thankfully it was able to repair the catalog. After the repair I noticed that the folder that the catalog was in contained a new folder, 'corrupt catalogs', and also temporyrepaircatalog previews plus temporaryrepaircatalog smart previews.

This was all fine until I later realized that all my preview and smart previews were gone a few weeks later. I went through the arduous process of rebuilding those afterwards which took a few days. The catalog itself is 1.84 gb and the temporaryrepair smart preview file is 128 gb. 

Unfortunately I got another notification that the catalog got corrupted again. It was able to repair itself again thankfully, however, my question is this:

Is it possible to "reattach" the smart previews that were previously used with the catalog so I don't have to go through the long process of rebuilding again?

Which files do I need to keep? Can I trash the 'corrupt files' folder? What about the previews file? There are two--one with the original name of the catalog plus the temporaryrepair previews.

I have a backup from a few days ago that I can use if needed as well.

Thanks very much and happy holidays-

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