I have an empty 3D model that references two other DGN files containing Structural members. I then place a Plan Callout using a Structural drawing seed that completely encompasses the referenced geometry. While I can see the results of that Saved View when applied in my 3D model, when I open the Drawing Model all I see is a grid, none of the referenced 3D geometry displays.
When the Structural references were attached to the master 3D model, the "Ignore Attachment When Live Nesting" option was enabled, preventing the Structural members from displaying in the Drawing Model.