This is the St. Vincentian tradition of "Rolling River," at least in the lyrical theme. There is no "Shenandoah" in it—which may seem just a pedantic point, since the song does belong to the family of so-called "Shenandoah" songs. However, at some point in the Anglo-American popular discourse, the oral tradition got funneled into one predominating interpretation of the song, where, among other things, "Shenandoah" is assumed to be the subject. In this orally-maintained Caribbean rendition (e.g. documented in the early 60s by Roger Abrahams), we have a chance to see through that fence that has been put around the song. Taking up a nearly identical theme to "Sally Brown," the men sang of "Sally," "Salambo" (sic), and "seven-long-years."

The Fishermen's Friends group looks to have taken lyrics from the St. Vincentian tradition and mixed it into the standard "Shenandoah" style. Not sure where they got the idea of sitting around and singing this while feeling "miserable." Sounds like something just made up from the fact of the word "misery." The Vincentians don't paint it in that way (?). In their recent/current narrative, the whalemen particularly ascribe this song to the (actually rather happy) event of catching a whale after a long time, and it would be sung during the heavy task of rowing back to shore with the whale in tow. These songs are "always" work-songs, presumably sung in full voice.


Here's the whalemen of Barouallie, St. Vincent doing a facsimile of rowing while singing the song. The song was a staple during their whaling days, and I was always curious to see how they would fit this decidedly non-rhythmic tune to the rhythm of rowing.

https://youtu.be/_6rrzgwwZMU
Shortly after that, I got a chance to sing it while rowing a whaleboat. It works, but it's hard to describe what the rhythm actually is; you just sort of time it to your breathing, and the phrase lengths. In my opinion, the phrases would be long, held out. In the Fishermen's Friends performance, they execute a rather "clipped" style of cutting choruses short, which I think would not feel right when rowing.

I gave it a personal shot at trying to sing it, here:
https://youtu.be/fhpmAjepDu8