A own .exe file. that means it is a program.
Anw what I know of it. It don't use all the info from iw4mp.exe it also use som own prog codes. ( blabalbal, nvm that for now)
So no, you don't need a injector for the ESP hack.
But I think its better to use the .py file.
that is a python file.
And they say that is alot saifer.
Hope it helps