If I understand you correctly, you changed the name of the file in Windows and do not remember what the file names used to be. You edited these in Premiere Pro, and now the project files you have created do not know where to find the video files.
Is that correct?
If so, I have what may be a simple solution for you.
Assuming you are not maxing out each file so they are all exactly the same duration, the number of minutes and seconds and frames ought to get you where you want to go. Almost as unique as a fingerprint on my PC, but I never capture a bunch of videos that are identical in duration - although it is possible to do so, I suppose.
Open a project file. Checking the properties of each file should reveal theoriginal file name as well as the duration, which is also available right on the thumbnail image (see the image below). Then open the Media Browser and look at the durations on each clip. This should be enough to help you either relink, or change the name in Windows back to what it was originally. This is still one at a time, but it should not take too long. A pen and paper might help with 50 videos.
Oh you are a genius! Thank you thank you thank you!!!!
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