The judgment at the Great White Throne in 20.12 is for unbelievers. It even indicates that by saying here and in verse 13 that they are judged on their works (which of course, will not be enough to save them). Believers have already been judged in verse 4 because this is called the first resurrection in verse 5. Believers are in the first resurrection.
You haven't proven that the Great White throne judgment is for unbelievers by scripture.
You've merely restated your belief.
Besides, works are instrumental in the description of the judgment in Rev. as well.
You haven't proven that the Great White Throne judgment is for believers.
If it's for believers and unbelievers alike, does that mean we will all be judged on the basis of our works at the same time? Because that is what the passage says. It says we will be judged on what is in the books about our works.