There is a new repo for this project - https://github.com/plutoniummod/t6-scripts
If you would like to contribute to this project first check out these resources that will help you in debugging decompiled scripts:
https://github.com/Scobalula/Cerberus-Repo: This is a decompiler that can decompile bo2 compiled scripts
https://drive.google.com/drive/folders/1Nwv3uGFwpopIMMXDVcZdG0iq2vQAVHc-?usp=sharing This includes:
Bo2 Dvars list
FastFile extractor so you can extract .gscs for the cerberus decompiler to decompile
Bo3 decompiled scripts
Bo2 zombies decompiled scripts
Bo1 full dump
An older Bo2 gsc dump from its initial release has comments from developers
GSC studio which has a built in compiler for bo2 scripting
This is the black ops 2 beta dump https://drive.google.com/file/d/1Rt3sAIoYhCgqhsotrElygta7-BXn-3ZM/view?usp=sharing