In my case both RCI and Carnival have my agent listed. Her agency even shows up at the top of the Carnival website. Yet they called anyway - breaking their rule.
I've recalled more information about this and I now remember contacting my agent after Carnival called and telling her about it. As you can guess she was outraged and contacted her sales rep. After that I received no more calls.
With RCI - after I had researched the cruise on their site I had my agent make the booking. The phone call came after the booking was made and appeared on the RCI website in my account. I find it hard to believe someone from RCI calling me didn't have my account information showing I had already booked the cruise via my agent.