Uhm, thats not how it works. It still works for me on EVERY server.
You run the injector, I use an injector I won't name because it's not popular at all. Then run Gmod. Inject, and the DLL should be named just gmodpickles.dll Then, in the main menu open the console and type sv_allowcslua and it should say below sv_allowcslua 1.
Now, you go into any server, type it in and see if it is on 0, then type just sv_allowcslua 1.
Then you know, run the script.
Otherwise, I can't diagnose anything else.