Thanks, Joe.
I've never heard nor seen the LP that it's on, but I was a member of Cyril's club for a while. I'm almost certain he SANG it as I wrote, and also as "you can keep your sherry..." and the 'jumped into a Dghajsa...' line.
Bighi Bay does appear on the Malta website, but not in the main 'bays' list, so unless you know how to spell it, you can't find it!

There's a difference between what he sang and what he recorded, sometimes, like 'Diesel and Shale' on 'Between Decks,' where he missed the last verse off the recording, but referred to it in the notes.
I have no memory of the three verses you mention, but I've only heard the song live. I'll include them in the song to my friend, and I'm sure Joe will include them on the D.T.
Regards, Chris.