The search engine suggests this somewhat more adult verse has never been recorded in the wild before. I've transcribed it from Jim Carter: Lonnie Donnegan and Me (ITV 1 17.4.2016)

One day whilst in a café
He spilt a milkman's tea
The milkman rose to argue
And he was six foot three...

The aninals in Australia
Are very, very strange
They've got one called a platypus
You'll find 'im on the range
You'll always recognise him
You'll know 'im like your brother
His platy hangs on one end
And his pussy's on the other

One point Lonnie's son Pete made is that this is actually a folk-heritage piece, as the music comes from My Old Man's a Soldier,

My Old Man;'s a soldier
Fought in the Battke of Mons
Killed ten thousand Germans
With only a hundred bombs
One lay here, one lay there, one lay round the corner
One poor soul wiv a bullet up 'is 'ole
Crying out for water...