Reaper Karthus Reskin Question

My understanding is that riot unified the splash arts from around the world. How come it's not okay for regular karthus skin, statue of karthus, and pentakill karthus to not show any bones but reaper karthus can? I thought they removed the bones because of some rules about bones being sacred in some asain country and they can't be depicted in the media. I guess my question is, is repear karthus a U.S only skin or did they forget to change that skin?