I think I see the problem. By linking your camera to the null object, you’re moving the camera to create layer rotation, but the 2.5d layers are not forward of the null object in 3D space.
If you move the 2.5d layers forward of the null’s position (z direction) you should start to see the behaviour you’re after.
If I followed correctly, you’ve built the box in c4d and are using 2.5d layers to add detail. You could also build 2.5d walls for your box too, and that way you wouldn’t need C4D and it might make things easier.
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