The code you have so far lists all of the part types, PCB decals, and CAE decals in the "Item" column of your Excel file. It doesn't show how any of them are associated with each other.
I don't know how to do what you want in VB script, but would the built-in report work for you? Go to the Library Manager, select All Libraries, Parts filter, and click "List to File". You can choose the attributes you want to include, press "Run", and save as type "CSV Files (*.csv)". Then open the file in Excel.