Your points  are valid reasons to include this information in the Purim article  Regarding the subject of this article it is a violation of WPUNDUE  Regarding item  it sounds like again FRINGE  Not that it is a fringe theory about the facts but rather a perspective of a fringe of the Jewish population the subject of this article and to put their perspective in this article is to violate WPUNDUE  Additionally you would need a WPRS for this  Regarding  I am not saying that Horowitz is not a legit scholar rather the view he expresses is a fringe one if not a lone voice  As such to include it in this article is to violate WPUNDUE