Yes, you got it! 
Really, all that is needed is probably just a URL method for triggering the narrative bot. That could be added manually to the hamburger menu, in FAQs and in other places where we explain how discourse works. Admins could also provide it directly in messages with users who are struggling with something, to encourage them to get to know discourse.
I also would value having a URL method (or any method) for triggering the narrative bot for someone else. I personally welcome new members all the time and am right now just going through a backlog, and would love to start the narrative for them and nudge them to take it in my message.