What do you need help with exactly? All mods that have ever existed should have their source available somewhere so someone with knowledge of how to build old versions should be able to build them. And btw there are many that don't support all platforms, only win32.

I have some mods you are missing, but not sure I want to help in its current state. It seems a bit disorganized, you're dumping old mods into one folder, leaving a huge number of DLLs and also junk files, it's not clear which ones are needed for which mods. You're also only archiving windows builds, not Linux, Mac, or what I consider to be most important, source code.

Archiving source code for all mods would require more experience with git though. But it would be nice if there was a branch for each mod's source, then the main branch has the binaries.

But also I'm not sure if GitHub rehosting is the best option for preserving mods. You should definitely have local copies for when links go down (which is what I've been doing for years). But a directory for the active links is a good thing too, like what @Mrprocom did here - https://mrprocom.github.io/projects/tptreference/#mods

My mod has every historical version preserved here already, with source code here, both dating back to 1.0. So in cases where mod owners like me already have it covered, it's probably best to link to official sources. Your link will go out of date as soon as I update my mod next.