The first thing I would do is to try it without the "SpongeBob strap screen", as your problem has to do with the strap screen. The other stuff you mentioned shouldn't make that happen.
It was the first thing I deleted when this stated happening. It didn't fix it, unfortunately.
I don't think it's the strap screen, though. Not if it's the one with Wombo and Imagination, since I had before used that in both Gecko and Riivolution.
When you say that Brawl doesn't load, do you mean it doesn't ever go to the main menu, as in it does a freeze or silent freeze? Or does it not load the hacks?
Brawl freezes on the dark screen before the strap screen. It doesn't make any noise, either. After I deleted the SpongeBob strap screen, I tried no "menu" folder, and normal Brawl's strap screen, neither worked.