That example url, has "gsuite" in it.
GSuite technically doesn't even exist anymore.
If I type in:
Into my browser when logged into my Workspace account the URL gets changed to:
You can't get your add-on Marketplace listing URL until it's published as far as I know.
I don't think that your Marketplace listing URL is even generated until your approved.
Maybe I'm wrong.
But you don't decide on what the Marketplace listing is, Google does that.
So, I have no idea what these people want.
I think they must not understand what they are doing.
I think these people are nuts!
But don't tell them that. Haha.
I think you'll need to explain to them that you don't understand what they want, and that you've looked at the documentation,
and also asked for advice, and nobody knows what they want.
Also question, why the example URL they gave has "gsuite" in it when GSuite doesn't exist anymore.