Hello Chris!
The process of georeferencing charts is not one that Navigraph can influence. It is up to Jeppesen to decide what charts get georeferenced and which don’t.
That being said, the reason why the parking charts have not received this treatment yet is most likely because they sometimes are slightly distorted to fit the frame at a readable scale, which renders the chart more or less impossible to georeference.
Regards,
Malte