All levels in the model are not exporting to .csv.
The reason that you don't get all the levels exported is because those levels are from DGN Libraries. In Level Manager, right click on the bar next to Name, Description, etc. so you see the list of columns to display in the Level Manager. Select Library. This will show you all the levels that are being used from a DGN Library. These levels are not actually in the file unless they are used to place an element in the file. The DGN Library levels will not automatically export unless the DGN Library levels are imported instead of attached.Also, when you open the file in plain MicroStation, the Architectural.dgnlib is not used since it is in the architecture dataset.