Yes. A "complete narrative" is basicly anything with a beginning, middle, and ending. That could be as short as one encounter, or as long as a multi-session campaign, including solo play games where play has a defined start and end.
I don't think you'll go wrong with following those old pre-written DnD adventures. To Change has over 10 sample adventures with player transformation as the focus, if you are looking for more modern examples.
For the last question, that just means that for each submissions, I'll be posting two free copies of my transformation TTRPG To Change, just as a small personal way to encourage submissions. Nothing that people participating in the jam have to worry about.