When they go the the trout farm, Jude Law's character finds Jennifer Jason Leigh's character operating on a biopod, but she repeats her lines just as one of the videogame characters would. As far as I can tell this had no import whatsoever on the rest of the story? Wouldn't her not being real be rather important?
As a side note, the last act of the film went a very different direction than I expected it to. I thought Jude Law's character would just go insane, and I expected an even more ambiguous ending.
I don't have my movie HD hooked up so I can't rewatch the scene rn. But I think the point was to make you think she was an NPC for a minute. Because they're inside the game on the stage, playing existenz, and in that game they're inside the squishy console. And that's after they were inside the minis, I think? So the idea was to get you to question if even the characters are really themselves or just part of the game.