The guy is super nice, I'm sure he'll try his best to help. I'm actually trying to sort this out so I'm kinda busy, but I'll try to talk to him!its okey , may you please ask him if could fix the issue by adding support ffx-ffx2 texture switch in his tools , since your already in touch with him
Also, did you actually try the beta build just for this? Maybe it works? Here's the link:
https://www.mediafire.com/file/3pj7x4t7tx4mboz/Custom_Texture_Tool_PS_v53.0.b03.7z/file