When I insert From SU Pro into Layout, it does not bring the most up to date model into Layout.
I have definitely made sure that I did save in SU Pro before trying this as well as shutting Pro down and starting it back up. I must not be saving it properly?
Again, you only send the SketchUp file to the LayOut project ONCE. If you modify the model, add scenes, or sections, you save the changes in SketchUp and then in LayOut, update the reference.
In your LO file, every viewport shows that you’ve modified the Camera properties for all of the viewports. Note the gray background and Reset button in the Camera section of the SketchUp Model panel.
By modifying the properties you are telling LayOut to ignore all camera properties in the scene in the SketchUp model.
In fact the three viewports in your LO file are ostensibly referencing Scene 6 but none of them show what Scene 6 in your SketchUp model looks like.
Also, since you’ve overridden the Camera Properties in LO, changing to a different scene won’t change the viewport to match the selected scene.
Best practice is to avoid modifying the Camera properties.
Here I’ve relinked the SketchUp model to the one you shared to make sure the reference is the most recent version. Then I reset the Camera porperties and changed the scene to Scene 7 which is the one that shows the section cut.