[Bug]: Game Crash if Dungeon Generation accesses namespace aside from `dimdoors`

[Immodial]

What happened?

I've been working on a datapack to customize the dungeon generation, but whenever it generates the dungeons it crashes and makes the world completely inaccessible (because it will continue trying to generate the dungeon) until the datapack is removed and the "please report this bug" handler can activate.
From my testing, this could just be reproduced by moving the "example" with a purpur hallway into another namespace, renaming the references to it to match that namespace, then creating a dungeon with dungeonGroup:"other:example", which then bricks the world until you undo the change. Even if use of other namespaces never becomes a thing, it'd at least be nice if it didn't crash.

Mod Version

6.1.1-1.21.1-neoforge

What versions of Minecraft does this issue happen on?

No response

Log

The game crashed: colliding entity with block
Error: java.lang.AssertionError: java.lang.NullPointerException: Cannot invoke "org.dimdev.dimdoors.pockets.generator.PocketGenerator.getWeight(org.dimdev.dimdoors.pockets.PocketGenerationContext)" because the return value of "org.dimdev.dimdoors.pockets.virtual.reference.PocketGeneratorReference.peekReferencedPocketGenerator(org.dimdev.dimdoors.pockets.PocketGenerationContext)" is null