Were the Avos Jewish? (part III - the parsha of the mekallel)

We have been discussing the machlokes Chachamei Tzorfas and Ramban with respect to whether before mattan Torah there existed a status of Yisrael, or everyone had the same din of ben noach. The Torah introduces the parsha of the mekallel by saying “vayeitzei”, he went out. Rashi cites Chazal who explain that the mekallel “went out” defeated from the bais din of Moshe Rabeinu where he had gone to press his case for a place in the camp of Klal Yisrael as a full Jew. Apparently, his court case revolved around the very issues raised in this machlokes Chachamei Tzorfas and Ramban. Based on this, suggests the Malbim, Rashi’s reference specifically to the “bais din of Moshe”, not just any court, is intentional and meduyak. Recall that in parshas Shmos Moshe killed an Egyptian for striking a Jew. From that episode Chazal derive that any nochri who attempts to strike a Jew is chayav misa (Sanhedrin 58b). This conclusion would only have been warranted if there existed a distinct status of Yisrael even before mattan Torah! Therefore, the mekallel confidently assumed that Moshe would side with his claim. (As to why the mekallel was wrong, at least one approach should be obvious from previous posts, and there are others - I’ll leave it to you to work out :)