The Coopordie.bat is in the zip file you have downloaded here :
http://www.coopordie.com/quake2/?page=downloadIn fact it is initially named "coopordie_edit_me_before_first_run.bat", and like you have probably guessed, you need to edit it the first time you run the game.
Replace "your_name" and "your_password" with your own name and password, and in your case, change quake2.exe with EGL.exe.