You did x -> guy was recruited
You did y + recruit anyone cheat -> guy was not recruited
Now you conclude that the recruit anyone cheat was not part of it. That sounds like flawed reasoning to me.
Being able to recruit a non-homie without the "recruit anyone" cheat sounds very unlikely to me. Rather, I think that you did something
plus the "recruit anyone" cheat. You need to experiment more, then, or question if your memory might be false (as in, it is impossible, your memory mixed up things).
Edit: I have read the mission script and it says that the witness is (unless he is dead) despawned at the very moment you fail the mission (resulting in a driverless car "driving" down the mountain
), which is unavoidable since it is 100% coupled with the "Mission Failed" text showing up.