The Text of 2 Samuel 6:21 in the Masoretic Text and Greek Codex Vaticanus being "vastly different texts"

Commenting on 2 Samuel 6:21, Daniel E. Fleming noted that:

 

The Masoretic Text (MT) and Greek Codex Vaticanus (LXX^B) present vastly different texts, and “the people of Yahweh” are only in the MT:

 

MT: Before Yahweh who chose me over [lit. ‘more than’, mē] your father and over all his house to command me chief [nāgîd] over [‘al] the people of Yahweh, over Israel, and I will perform [śḥq] before Yahweh.

 

LXX^B: Before the Lord [=Yahweh] I will dance. Blessed be the Lord [=Yahweh], who chose me over your father and over all his house to appoint me leader for his people, for Israel. And I will perform [παιξομαι, for Hebrew śḥq] and the dance before the Lord [=Yahweh] (Daniel E. Fleming, Yahweh Before Israel: Glimpses of History in a Divine Name [Cambridge: Cambridge University Press, 2021], 194-95)