Judaism refers to the first six books of the Bible as the Hexateuch, for the thematic reasons you mention.
The Pentateuch certainly ends in an unsettled way (no pun intended) because the Israelites have not made it to the promised land, God’s promise to Abraham is unfulfilled in the Torah.
And, in fact, Deut 34 concludes in a very ironic way, by stating that since Moses’ death, there had not arisen in Israel another prophet like him. So, the first problem is the meaning of “like him.” How do you classify Moses, to begin with?
The second problem is that back in Deut 8 or 10, Moses foretells that there* would be * a later prophet “like him.” And, in that same chapter, it says if what a prophet foretells does not come to pass, then you should not “fear” him. So, why do Jews regard the Torah so highly, if Moses’ prophecy has not come to pass? Since the Torah itself says that this prophet has not come, then why doesn’t the Torah collapse on itself, so to speak?
this would be similar to a cult leader today who has predicted the end of the world today. Maybe things haven’t gone so well, the usual 250,000 people die every day for all sorts of causes, but the world did not actually end, so this cult leader is discredited. Why wasn’t Moses discredited?
I suppose there’s two schools of thought: 1) the Jews are still waiting for this prophet, so there’s no problem (recall the Samaritan woman at the well asks Jesus if he is the long-awaited prophet, to which Jesus replies that he is). 2) Now, from a Christological point of view, Jesus is the prophet, so – whew! – Moses is safe.
so Judaism BELIEVES that Moses will be vindicated, but they have not proof of it, even in Joshua. In his series of books (Jesus of Nazareth), Pope Emeritus Benedict XVI says that Jesus is the new Moses – amongst other things, he is a law-giver as Moses was.