Those lyrics, Dorothy, are really interesting. It would be good to know how long ago your brother started singing them. They come from all sorts of places - from recorded songs, from the Sandburg versions . . . and even, judging by the second-to-last verse, sort of made up but similar to earlier verses.
The first two verses, though, first appeared in 1930, when the company Denton and Haskins published a version of "St. James Infirmary" to rival the stranglehold Mills Publishing had over the song. On the inside front cover they included traditional versions of the song that had been collected by the poet (and folk song archivist) Carl Sandburg. But what they were selling - or, once Mills launched a cease and desist lawsuit, trying to sell - was a new version of the song, arranged by Claude Austin with additional lyrics by William J. McKenna.
I have never encountered a recording of this version of the song. In fact it died pretty quickly once the legal wrangling ended. Still, there was a brief time when this sheet music was circulating, probably mostly around New York City. Obviously parts of it found their way into your brother's song, which is an example of the many guises "St. James Infirmary" has assumed in its adventurous life.