You cannot request your claim to be submitted for another account. If you submit a claim trough the Customer Service section, that claim is automatically submitted for the account you are logged in on regardless of what you mention in the additional information section.
If you want to submit a claim for 5911xxx, you have to do it from the login screen of the game, and not while you are already logged in on another account. This is how the account recovery system works, and this is not something you can change.