These type of monsters have quite a special case to set up materials. For this model, it needs the texture "EnSatanI00_BaseColor", "EnSatanI01_BaseColor" and "EnSatanI02_BaseColor" applied with "EnSatanI00_ALB", "EnSatanI01_ALB" and "EnSatanI02_ALB" applied on top respectively. Also "EnSatanI00_MSK" and "EnSatanI01_MSK" are emissive textures.
I hope this is enough to know.