http://www.slashfilm.com/carrie-fisher-in-the-last-jedi-send-off/
I think he just means that her presence is really at the heart of the film, and that this movie sends her, as an actress, out on a heartfelt high note.
I don’t think any of his statements are meant to be indicative of whether or not the character makes it out of this movie alive and/or appears in episode 9.
Just my 2 cents though