I just used a custom stencil PPM and i can just choose which objects are included by changing their customDepth stencil value. Much easier than going through all the faff trying to work out why the render passes don’t work.
I can then turn it on and off in the post process volume if i need it. Annoying that this is necessary but I’m not spending any more time trying to work out why the movie render graph method is not working!