Yup definitely the Eboot.
Download this tool:
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Then after that grab the games default multiplayer file "t6mp_ps3f.self" and use the tool to decrypt it to elf.
Select the following options:
* Disable Protected Character
* Anti-Ban
* Probation Bypass
* Cheat Protection
After that select the build type of your game:
*BLUS31011
*BLES01717
*NPUB31054
//If your using DEX select:
*DEBUG
The problem was you were using Its_Jewelz eboot which is a very fucked up eboot. After your done doing all that, build the eboot, and take that eboot and replace it with the other eboot. There will be no more blackscreen and no more "Press []" for everything if done correctly.