Porting Forge Optifine Resource Pack to Fabric CIT Resewn Resource Pack

There is a datapack / resource pack for Minecraft Forge 1.15.2 that I updated to Minecraft 1.20.1 successfully using the Misode online upgrader. This pack adds a variety of balls to the game allowing the playing of sports in the game. The balls are all modified Slimes. Upon running the modified and upgraded packs in Minecraft Fabric 1.20.1, the modified Slimes are working correctly, and the items have appropriate icons too. However, the textures of the slimes themselves are not working properly. I assume this is due to them being Optifine textures running on Forge 1.15.2. I need to modify the file structure appropriately for the textures to show up in Fabric 1.20.1. I want to use CIT Resewn for this, with the file system and code appropriately changed from Optifine to CIT Resewn. However, I am not sure how to proceed.