Worley's Cave is present in any other World Type (Default, Large Biomes, Amplified, Customized) with CubicChunks enabled except in the CustomCubic World Type. In this World Type only regular cave structures do appear.

From what I can tell, the custom cubic world type replaces caves with its own configurable cave generation, which doesn't throw the normal event that lets other caves take over. This probably means that any cave mods won't work in a custom cubic chunk world (worley's, swiss chesses, custom cave gen, quark big caves).
Not sure there's much I can do here. I would try reporting this to Cubic Chunks, but it may just be intentional on their part.