User blog comment:Kogath/Monster Hunter: World Discussion/@comment-33384696-20170921105328/@comment-5167887-20170921224920

Probably because Shen Gaoren used a Lao skull that was much larger that that of an in-game Lao-Shan. But that's the problem with all Carapaceons, and may be a minor design error, just like we assumed Monoblos could have two hearts because we could carve more than one.