So the Outer Gates in Deep Fairy. But Fairy borders the mortal world. The never-never encompasses everything else outside Mortal World. Which includes fairy. So The Outsiders can go to the Never Never. But fairy guards The Outsiders from the mortal world. So it's looking like a round ball with fairy surrounding and then a wall then never never? But..Or...
Or is there a whole in reality in deep fairy between the never never and fairy that the wall blocks. And must have a gate for balance. That they always protect. Grab cup of coffee discuss?
Unsourced assumptions:
1) Outside the Outer Gates remains within the Nevernever
2) The Nevernever includes everything outside reality- ie, is infinite
Proposal: There is an uttermost edge of the Nevernever, and that is referred to as The Outer Gates.
The Nevernever itself is something like the multiple universes theorem- it is all the parallel universes that could be. Call it the wave function of reality. The light cones, then, would be the Outer Gates.
This is also similar to the Chronicles of Amber, with its infinite number of Shadows between the two anchors of reality.
The real world - or in theory, real worlds- have substance and mass. Faery, with its breeding dependence, therefore has real non-ectoplasm mass- hence why you can trap the Fae in circles and they don't splort like Binder's goons- whoch one supposrs gives them metaphorical momentum against outside.
Fun thought for later: Does the war at the Gates reflect reality expanding?
Anyway, Outside is Outside. Nothing says it's in the Nevernever.