As for the GFDL. As I mentioned above. These are not some amatuers or startup companies. These are professionals. I think they know quite well what GFDL means. But on the other hand. They can also say: well, GFDL is an american licence, it has no meaning in China. So we don't need to mention it or to obay it.
Actually China is now a member of the Bern Convention. Thus they respect copyright, even foreigner's copyrights. Then, the GFDL can have full effect in China.