Since posting the LXX, DSS, MT and reconstruction of Deuteronomy 32:43, I noticed something in the LXX manuscripts concerning line 4. In line 2 it mentions the heavens and therefore the reading of angels is more likely original. In line 4, not extant in DSS or MT, the LXX Mss read either “angels” or “sons.” Since this line is talking about the nations the reading of sons is more likely the original reading in context.

Translation: “Rejoice, O heavens, with him, and let all the angels of God worship him. Rejoice, O nations, with his people, and let all the sons of God strengthen themselves in him. For he will avenge the blood of his sons, and he will render vengeance to his enemies, and he will recompense them that hate him, and he atones for the land of his people.”