Meself, for the 1825, 1828 dates, see above, May 23, 9:24 pm.

Admittedly it isn't clear that any rowers were singing. But the date makes the issue moot.

For the original printing of the 1829 song:
https://tinyurl.com/yxdus8us

C. F. Klinck, ed., Literary History of Canada (1976), vol. I, p. 182:

"It is not a translation of any known Gaelic song....There has been considerable debate about its authorship, but it was probably written by David Macbeth Moir as a result of letters sent to him by John Galt when he visited Canada in 1827."