There are two ways to bring 2D geometry into a 3D Scene, you can use the Import Reference 2D command or you can Import the file in the 2D Sketch. If you want the 2D geometry to appear in the ICD file along with Views, you will need to use the Import option in the 2D Sketch. Once the geometry is in the sketch it will transfer to the View in the ICD. Geometry imported using the Import Reference 2D command will not appear in the ICD Views.