Piglins / Zombified Piglins do not render Correctly with Mashup Packs

After purchasing and enabling the 4J Studios Greek mashup pack on my world, Piglins and all their variants are not rendering correctly. The Piglin and Zombified Piglin have large, completely invisible sections of their bodies, with incomplete and misplaced textures in the areas that DO render. The Piglin Brute renders correctly, but has yet to receive its updated texture for this mashup pack.