You didn't offend offend me with your initial response. My bad. Perhaps I was being a bit to flippant. Yes, I understand, new user, changing priorities. No probs! Just couldn't tell if we were getting you closer to the goal or not. Evidently not, but then we don't know exactly what you were seeing with the Go Locker app.. evidently the EE was still there, and something didn't line up with the window on your flip case (I'm guessing).
As for your most recent reply - you didn't offend me with that either. I'm old, crusty, thick skinned... Really, people like myself honestly just want to help you enjoy the potential of your device... not put you down. If you feel I did, I apologize.
As for the LG Optimus Lockscreen, that doesn't look like it's going to work... I just tried it myself. My hunch is, a lockscreen replacement isn't going to remove the carrier identification. You are sort of off on your own w.r.t. requirements for this particular aspect of your device's operation, and only experimentation is going to yield a possible solution or more insight.
BTW, I was serious about writing a developer (more than likely will have some detailed knowledge in this area), and then if you can't get what you want and if you are a programmer, maybe you'd want to give development a try.