Scientists assume they spoke Hurrian based on their names, all of their names in Hittite inscripions were Hurrian. This doesn't mean that they were Hurrian since Hittites had Hurrian names as well. You're contradicting yourself. On one hand you speak of the lack of evidence regarding Hayasa (amateur linguistics are not evidence) on the other hand you propose to place it on an equal footing with a quite logical hypothesis (Phrygian) supported by Classical sources, lingustics and a good number of modern scholars and the Gamkrelidze/Ivanov theory. How should it then end up on an equal footing with the other two? Other than the similarity of the names Hay and Hayassa we have nothing else. Feel free to write a paragraph that suits you and present it here though.