I would implement a new AuditStrategy (extending DefaultAuditStrategy) like this:

• initialize: Reading external configuration using the ConfigurationService by the serviceRegistry
• addAdditionalColumns: Adding new columns just like the ValidityAuditStrategy
• perform: Populate the additional columns by putting them in the data-Map and calling super.populate()

That's how to populate the data. I haven't tried already if I can access them by implementing an AbstractAuditQuery.