The date is close. Scholars usually place P.Oxy. XV 1786 at the end of the third century AD, around 250 to 300, so "late 200s" fits. The papyrus was found at Oxyrhynchus, published in 1922, and is kept in Oxford. The Wikipedia article on the Oxyrhynchus hymn gives the same description: the earliest known Christian hymn manuscript with both words and musical notation.
The English in the post is a loose paraphrase, not a translation from the papyrus. The surviving Greek opens with an instruction that silence should fall and that the bright stars should not sound aloud, then says the springs of the rushing rivers should be calm. The Trinitarian line, asking every power to answer "Amen, amen," is close to the post. The lines about winds and kings differ between translators, and the papyrus is damaged in places. A 2025 rendering by John Dickson, reported by ABC News, has its own wording, including "calm the winds" and "let kings bow." The closing doxology is the least certain part, so read the Greek and a scholarly edition, such as C. H. Cosgrove's 2011 study, before relying on any single English version.

