I got disillusioned trying to load models thru monogame and wrote my own loader and model classes using the nuget open assimp importer directly which can load blender 2.79 generated fbx files directly.
I purposely separately loaded the textures though then attach them to the model when i load the fbx.
I was getting that renaming on the xnb’s as well when i tried to do it thru monogame and other problems also like missing data that i needed.