If you want to publish 9 movies each on different screen, why do you need to create a videowall?
Just publish different content on different monitor and schedule them. This way you can run 9 different movies on different monitor.
If you plan to play each movie on 3x3 video wall, then make a video wall and create video wall content (select 9 movies) and publish it. It will play all 9 movies in sequence.
Let me know if you still *CENSORED* some problem.