Well, do it yourself then. Quick tutorial.
1- Download Cheat Engine if you don't have it already. Google will help you find it.
2- Attach CE (Cheat Engine) to the game process, iw4m.dat.
3- Click on "Add address manually", write 6FABDF4 and hit Ok. See image below.
4- Double click on the value, 9 by default, and write 4 on the box that will appear.
PS: To Coders, I know there's a dvar for fullbright, but fuck it.