Things not generating.

A couple of end biomes are not generating but it shows the blocks in jei but went hunting for it and found that they couldn’t/didn’t generate. The specific biome I was looking for was the End Wilds Which has a nice purple wood I was going to use for a base. The couple structures I was looking for were from ars nouveau, only 1 out of 3 could generate being the wilden dens and the ones that couldn’t generate were the Arcane Libraries and Nexus Towers. I tried using commands and the natures compass to locate the biomes and just commands to locate the structures not sure if there are more that can’t or don’t generate.