[solved: better biome blend incompatibility] Certain Blocks Voided (Iris/DH)

Hey all, messing around with a bunch of mods for a pack and encountered some weirdness. Select blocks become voided. I've seen one other person with a similar issue, but everything was voided, not just certain blocks. Please let me know if you find what's causing the weirdness. Log file attached. The issue occurs both with and without shaders enabled.