St Vincent and the Grenadines is a “Commonwealth realm” - a country where the Queen is head of state. In the year 2016 they changed their oath:
“I, [name], swear to be faithful and bear true allegiance to St Vincent and the Grenadines, uphold and defend the Constitution and the laws of St Vincent and the Grenadines, and conscientiously and impartially discharge responsibilities to the people of St Vincent and the Grenadines. So help me God.
There’s no reference to the Queen at all.