I would suggest keeping them, but as things that the followers of Nerull tell themselves -- which need not have any relation to how things actually happened.One thing I don't like about the article is that it kinda takes away some of the Raven Queen's awesomeness. Earlier versions of the story had her ascend to godhood and steal the Death domain on her own, IIRC. Here the one who does that is Nerull, with the Queen only managing to gank him because she had the help of three other gods and possibly of a curse. The impression here was that the Raven Queen was just a tool, which I don't like. So in my games I'd remove these particular details.