Its only natural that, now IRCC will be extra cautious while dealing with such cases where the applicant has obvious military connection - specially after the recent incident in Vancouver where a Canadian Citizen was murdered allegedly by someone connected to the military in question. After this incident, nobody will dare to implicate themselves with such applicants, neither Canadian PM, CSiS chief nor the military chief.
What is surprising here is your application is being processed for 5 years, the timeline spans beyond all of these recent incidents. And one also has to wonder that if their application is almost put in a freezer,they have gone to the court and even court told them to keep waiting....why are they still pursuing it?
(though its not digestible - Mandamus is by definition for such applications, where CIC did not process it, specially if the application was in background check for ages and total time passed is multiple times of the average case processing timeline).....
5 years is a long time - and most immigrants will pursue other options - US, UK, Australia, Germany...............Or at the very least discuss their case with a lawyer instead of this forum.
Something doesn't add up here. But anyways, good luck with your pursuit.