They were reciting Psalm 121 responsively. No names mentioned in the video, but probably recited quitely beforehand. Don’t know where you can find transliteration, except in Chabad English Language/Hebrew bilingual prayer book published by Kehot, available on-line at Chabad.org. No guarantees that it will have that Psalm transliterated, though.
Thanks. I should have thought about it, since the Rabbinate had asked people to recite Psalm 121 when praying for the boys. Thanks again.