Hextech repair tool STILL very dangerous and volatile, do not use

The other day league wouldn't open, saying files were "corrupted and unable to be repaired." After trying several times and playing around with it, I couldn't get it working, so I eventually downloaded the hextech repair tool.
I started that up, and after a couple hours it was still in the "reinstalling" phase. So i left it on overnight, and the next day it had made no progress. So I restarted my computer, and I just tried opening league which mysteriously worked again (aka, there was no problem to begin with).....but my WHOLE secondary harddrive was wiped.

I hope to Jesus H ****ing Christ that I only had games on there, but I will never know for sure whether or not league permanently deleted many archived years of my life will I? I usually kept all my old computers' contents zipped up on my secondary harddrive in case i ever needed anything, but now I guess that's gone.

I have seen multiple threads of people who had the same thing happen to them, and it seems to be because of the fact that league was installed into the same base folder with all my stuff in it, instead of it's own separate directory on the harddrive. Whatever the reason, this is SERIOUSLY messed up and DANGEROUS.

So if any of you out there are about to use the Hextech Repair Tool, DON'T. Riot, you gotta fix this. I guess I'll spend the next few days redownloading every game I've ever had and pray that all my savedata was on a cloud. I mean riot probably can't do anything for me, but hopefully this will save someone else from losing their actual entire computer with no warning.