Quisling the nazi failure

They don't. They end up in the lowest circle of Hell.

Where there is wailing and gnashing of teeth

I probably don't get the references, but I think where you end up depends on who you're defecting from and why.

In "Dante's Inferno", the lowest circle of Hell is reserved for the Faithless. At it's heart, Satan is frozen, and trapped within his three mouths are the three most famous traitors in classical history: Cassius, Brutus, and Judas Iscariot.