It might be because we are a smaller island with a more concentrated folk tradition?
Perhaps it's because we had a larger proportion of "gentleman" academics attempting to catalogue traditions?
Maybe it's because in Britain, field recordings were made for the purpose of transcribing tunes and lyrics with a view to publishing, or comparing to earlier published sources?
Maybe it has something to do with the fact that many recordings of American music were a commercial product, rather than an academic study?

I can't help with your lyric at present, but don't think we are ignoring you.
Sometimes Mudcat comes up with the goods in sewconds, other occasions it takes a bit longer. I once put out a request for a monologue in September 2001. The words finally appeared in July 2007. It took a while, but I now have words plus information about the author.
Best of luck.
Quack!
Geoff the Duck.