The VGDS is coming from the scenery, and the marshaller is coming from GSX, since GSX cannot possibly know automatically the scenery has its own VGDS without a customization for that airport.
Since you were used to AES, such customizations required payment for each airport, in the form of credits.
Instead, with GSX, you can tell it yourself about an airport the first time you use it, with the parking customization page, which has an option to disable the marshaller.