The 3D model .pdf doesn’t seem to work in a web browser. It works for me using Acrobat viewer application and takes a while to load. Note that there’s a dialog box in Acrobat viewer that you have to give permissions to view. I also had to left click in the blank window to get the image to become visible.
The 3D drawing depicts all components as populated but there are some components that are not populated on the production build. You can reference the BOM (Lists only populated components) or schematic (DNP in component properties indicates Do Not Populate on the production board).