Is Deuteronomy 32:8-9 Earlier Than the Rest of the Song of Moses?

Deuteronomy 32:8-9 states (and here I will be using the New Revised Standard Version):

"When the Most High apportioned the nations, when he divided humankind, he fixed the boundaries of the peoples according to the number of the gods; the LORD's own portion was his people, Jacob his allotted share."

I think that Deuteronomy 32:8-9 is from a source that is earlier than the rest of Deuteronomy 32:1-43, which is the Song of Moses.  I don't know if anyone else has said this----I wouldn't be surprised if someone has----but it just seems to me that the content of Deuteronomy 32:8-9 is at odds with the rest of the Song of Moses.  At the same time, however, I make this statement while holding specific assumptions about what the content of Deuteronomy 32:8-9 actually is, and perhaps it would fit right into the rest of the song were I to have different assumptions.

Allow me to first share what my assumptions about Deuteronomy 32:8-9 are.  I base them on things that I have read and heard within academia.  First, the Most High (Elyon) is different from the LORD (YHWH), and the Most High is dividing up the nations among the gods and is giving Israel to the LORD.  Second, Deuteronomy 32:8-9 indicates that it's all right for the other nations to worship their own gods, since these nations belong to those gods; Israel, however, is allowed to worship only her god, namely, YHWH.

These themes appear to contradict what's in the rest of the Song of Moses.  First, whereas Deuteronomy 32:8-9 presents the Most High dividing up the nations and giving Israel to YHWH, as if Israel existed before YHWH became her god, Deuteronomy 32:6 affirms that the YHWH created Israel.  Second, whereas Deuteronomy 32:8-9 appears to deem other nations' worship of their own gods to be acceptable, much of the Song of Moses depicts Israel's oppressors as foolish.  This judgment extends to their worship, for Deuteronomy 32:31 says that their rock is not as our (Israel's) rock.  A significant message in Deuteronomy 32 is that YHWH will defeat Israel's enemies in order to glorify his own name, so that the nations would know about YHWH's power and supremacy.  Why would the Song of Moses incorporate an earlier piece, if it contradicted its ideology?  Because Deuteronomy 32:8-9 affirms that Israel belongs to YHWH, which is a significant theme in the Song of Moses: Israel belongs to YHWH and not the other gods, yet Israel has strayed from YHWH.

Now let me critique what I just said.  First, I'll do so while retaining my assumptions about the meaning of Deuteronomy 32:8-9.  Perhaps YHWH was the creator of Israel, not in the sense that he brought the Israelites into being, but rather in that he made Israel what she was as a nation: he delivered her from slavery, gave her laws and a system of authority, and gave her land.  Professor Bernard Batto said in his book, Slaying the Dragon, that the story of the Red Sea (at least according to one of the biblical authors----I think it was P) was a creation story: in the same way that God in Genesis 1 split the waters and created the cosmos, so likewise did he split the sea and create Israel.  There were already Israelites, but YHWH fashioned them into a nation and in that sense could be called their creator.  Could not Deuteronomy 32:8-9, therefore, be consistent with the notion in Deuteronomy 32 that YHWH created Israel: the Most High gave Israel to YHWH, who made her into a nation?

Regarding the issue of Deuteronomy 32:8-9 deeming foreign worship of the gods to be acceptable, perhaps that is the case, and yet that is consistent with believing that the gods of the other nations are not as good as YHWH, the God of Israel.  Israel has the better deal, the Song of Moses may be saying, yet she chooses to worship other gods!  Moreover, maybe Deuteronomy 32 tolerates the foreign worship of other gods, while still deeming it to be foolish, since YHWH is superior.

Second, I'll critique my assumptions about Deuteronomy 32:8-9 and see where I end up.  Maybe Deuteronomy 32:8-9 does not regard the Most High and YHWH as two distinct gods, but rather as the same god.  In this case, YHWH created Israel and the other nations, and took Israel for himself.  On whether Deuteronomy 32:8-9 deems the foreign worship of the gods to be acceptable, my point here is the same as what I said above: it may regard it as acceptable, yet as a raw deal, and as foolish, since YHWH is superior.