Hanlon's razor applies here. If there was truly something nefarious going on, why would FedEx update the tracking status to say that the packages were re-routed? Why not just say they were held up in the sending or receiving country?
Potential reason - they do not have a system that can split public/secret stops. They need tracking to be available for internal purposes (actual delivery) but never built the filtering features. (Or there is, but needs boxes to be checked explicitly and the box wasn't checked. Is there anyone from FedEx to throwaway comment? :-) )
No. If they want quiet intercepts, that's what they get... even if it means "slow down conveyor belts and post agents to manually read every incoming package label before it hits the scanner".
This was either unrelated or an intentionally loud message.