Try the Atama material and Shader1; also, instead of directly replacing the material and shader, right click the mdl0 and add a new shader and a new material and replace the new ones with the exported ones, and delete the old ones (and reattach the new shader to the new material and the new material to the polygons; also make sure that the texture set to the material is the right texture
This should work, because I have only ever run into problems when directly replacing materials and shaders, but I have not yet had problems with replacing completely newly created ones
Went back to the file and changed the material's assigned texture to WolfFur, and got the same result.
HOWEVER, I found what the problem was... for real this time,
I went and looked at the basic FitWolf00 Head texture, and exported that. As it turns out, BrawlBox cut out parts of the texture, making areas of the png file transparent. So I filled those two holes up with paint.net, and it worked. (This was done with v 0.71)