If I’m not mistaken, I was just reading recently that rabbinic Judaism regards the Psalms of Solomon as a sacred part of their textual tradition, but I have no idea how they view later discoveries.

It would be interesting to know if institutional Judaism is more or less resistant to new discoveries of ancient texts.

I don’t think Judaism has quite the same tradition as Christianity regarding the hand of God in the preservation of the Canon. And of course, the Jewish Canon is different from the Christian Canon even in places where they overlap.