As for Shwmae, Dilwyn, that’s explained in the video.
Basically, when I got home from fishing my wife brought my dog to the door.
I speak to him in Welsh and I said ‘Shwmae, Dilwyn. Noswaith dda.’
It means, ‘Hello, Dilwyn. Good evening.’
I didn’t realise there was a man walking past when I said it and he thought I was talking to him.
He said, ‘Hello’, which bear in mind I live in the middle of England, we have no Welsh people, never mind speakers in the area, and I doubt whether his name is Dilwyn.
Not laughing at him, of course, just thought it was funny.