How you do that, is in the field, input - See Full disclaimer below
Then, for each chapter, you have your disclaimer as the first part of the story, and as you need to add names, you do.
Now, if the reason is just to make a verbose disclaimer which simply won't fit in to the field, input - See full disclaimer below, Chapter 1.
As long as there are no changes to people involved and what not, it only needs to appear in the one chapter.
Technically, that part really only applies to standard fanfiction, as with real person based fiction with many people, your disclaimer and it's needs are going to be very fluid, depending on if you're adding more to your story or not. Which is why you'd simply copy/paste from your first chapter, insert it to the next chapter and make additions as needed.
We even had one author who was adding/deleting people as she went. So, what she did, was put the disclaimer at the end of her last chapter, and used the field to tell us that's where it was. A bit unusual for placement, but certainly workable.