As reported the UK plod consulted Attorney General/DPP but were unable to press charges because the offences were committed outside UK; they passed all the evidence to the German police who similarly could not do anything because of the rules regarding UK service personnel at the time of the offences, so it went to RAF plod who under the relatively recent changes could press charges.
Sounds like the UK civil police did a good job in evidence gathering in the first place so that there was a case to answer. Similar hopes that the victims lives have not been permanently affected.