Rebekah, I have neither the Howell nor the Powell arrangement of that carol, both mentioned in your post. I have two copies of The Angel Gabriel, in different keys, and with different words and different melodies. If either of these is similar to what the choir is singing, and might possibly help you, just e-mail me and I will send you electronically either version A or B, described here: A: from ChristmasCarolMusic.org – free Christmas carol free sheet music. Words: Basque carol. para. Sabine Baring-Gould(1834-1924). Harmonized by Edward L. Stauff. Key of G minor. Measures 1 and 3 are in 9/8 meter; the others in 12/8. Four verses, the first beginning “The angel Gabriel from heaven came…..
B: Organ arrangement. Five Verses. Key of E minor. “Traditional”. 4/4 meter. First verse begins: The Angel Gabriel from God was sent to Galilee…
This is not the Christmas story, but rather the story of the Annunciation.