Ignore my now deleted comment. I was looking at wrong datapack. I know where issue is

okay no problem, if u need any logs or something let me know !

v4 of datapack is now out to fix pillar supports not spawning

https://www.curseforge.com/minecraft/texture-packs/repurposed-structures-yungs-better-nether-fortress/files/4478435
https://modrinth.com/datapack/repurposed-structures-yungs-better-nether-fortress-compat/version/I4ZwYyOv