I do know that the tiff C outputs gimp cannot read. The reason is an index difference. Assumably from the tiff version change. C does support mtl files, last I checked. This is also easily correctable by using a text editor to change the texture path.The problem is what gets put in the obj/mtl file. You can output an obj from hex and C can read it. It usually ends up being a relative instead of absolute path, this causes issues. The other option is to put the textures, obj and mtl all in the same folder.

No need to think outside the box....
    Just make it invisible.