For comparison 4Q44 actually reads:
43 Rejoice, heavens, with his people,
and bow down to him, all gods,(divine ones) for he will avenge the blood of his sons.
It is often regarded as the volage, the source text, for the LXX. We can see now the LXX insertion of another line referencing angels in an attempt to redefine the 'divine sons' as angels. We can also see in this early 4Q44 form the use of 'sons' rather than "servants' as appears in the MT and SP. This looks back at the line above it. Thereby redefining the sons as humans, Israelites.
IOW there have been multiple attempts to rehabilitate the text. In the end, the edits contributed to a new Christology which ironically almost mirrored the original polytheistic form.
The Samaritan Pentateuch edits evens more aggressively, dropping the whole line:
Rejoice, O ye nations, with his people: for he will avenge the blood of his servants, and will render vengeance to his adversaries, and will be merciful unto his land, and to his people.