Give Credit To 7Swww.se7ensins.com/forums/threads/work-around-for-prestige-glitch-past-all-patches.834980/#post-6153019
Tutorial:
FWith High level account, Press A On System link, then create a game
With the lower level account, sign in, and then right away sign out.
With the player 2 controller, press A to sign in
With the high level account, press B to sign out
With the player 2 controller, sign into the high level account
With the player 1 controller, sign into the lower level account
- You should now be at the Multiplayer menu.
With the high level account [Player 2 controller], Press A On System link, and then create a game
With the lower level account, then sign out straight away
With the lower level account, press A to sign back in
With the higher level account, (Player 2 controller) press B to sign out
Now just switch the High Level account back to Controller 1, And the Low level account back to Controller 2.
Press Start and the low level account (Player 2 controller) will glitch out and be the same level as the high level account
Back out to the multiplier menu with the glitched account, and then go back to system link
Wait until the name stabilizes to your name, and a couple seconds after it will kick you to the Multiplayer menu
Press A on xbox live, and get in to a game for your rank to sick.
I just did this on patch 23.432.11. This is basically doing the glitch in system-link, which they didn't patch, and then going to xbox live after the account it glitched to get the rank to stick. There may be an easier way to do this, but this is exactly what I did and it worked.