Before his disgrace, Andrew often used 'friends' to promote his causes in the media, for example, regarding the status of his 'blood princess' daughters.
More recently, royal stories quoting 'friends' are ones about Harry and Meghan.
Harry and Meghan have gone further than Andrew though, feeding grievances to Omid for Finding Freedom and this latest book, as well as making various unpleasant claims in Spare. They've also had form for trying to manipulate the RF via their PR in the media (mostly unsuccessfully, but they keep trying).
Given the predictable timing (Charles birthday, Crown launch, various photo Ops for Harry and Meghan this week and last) I personally find the idea that the media 'made up' the Sussex birthday phone call or Sussex hints for a Christmas invite - rather than these originating directly from Harry and Meghan themselves - a bit laughable.
Most people see straight through their antics.