So where did it all come from? Do you know? I did not. All I could tell was that it was NOT the 'Berlin Rag' that was composed by Bernie Pearl.
Well, Robin has kindly let me know it was composed in 2016 by Ewan Bleach - who of course had been a member of Tuba Skinny for a while. Well done, Ewan! And thanks, Robin. Ewan composed it for the band Frog and Henry and they (without a trombone - unlike Tuba Skinny) recorded it in 2016 on their CD (it's the very first track):
What's more, their version is on YouTube: https://www.youtube.com/watch?v=w_hlXHBianM&feature=youtu.be .
At the top of this article you can see the poster produced to go with this tune. Frog and Henry Music have very kindly sent it to me.
The book 'Tuba Skinny and Shaye Cohn' by Pops Coffee is available from Amazon.