Confirmed this method also works to unban CSR Racing 2 in iOS 10.2 (iPhone 6), however, because CSR is a Natural Motion games, you need to create few more of the SQL syntax/code for all of the DB entries in the keychain. Once you are done, restart (not respring) the device. The CSR Racing account is changed and then you will start all over again. If you want to connect the game to the iOS game center, I recommend to keep the new local version, to avoid being banned again.
The steps:
1. Uninstall CSR Racing 2 from your iOS device
2. sign out game center
3. use iFile or Filza to edit the keychain (find and delete all entries with ".naturalmotion.customstreetracer2."
4. restart device (not respring)
5. install CSR Racing 2 --> do not login to game center yet, until tutorial is completed
6. sign in to game center
7. when asked in CSR to restore cloud save, choose the local version
Thanks and I'm sorry if this post is misplaced, you may move it to the appropriate thread.
Cheers.
