Losing an aircraft under what should have been better than normal conditions is careless at best...
Three cockups happened simultaneously:
1. The Lynx crew lost track of Mother
2. Mother lost track of her Lynx
3. The Bag lost SA of the Lynx relative to Mother
Given the generally excellent nav kit on all three - all have GPS, the fact that all three are considered worked up and reasonably experienced, the chain of events leading to this accident may not appear so simple in the end.
Ultimately it will be (as it ought to be) the a/c captain who will carry the can - he lost his a/c, which was fully serviceable, by allowing it to run out of petrol.
As for the chimps who question the need to operate EMCON silent, they might like to think about what all these assets were doing at the time. It's not rocket science to figure out why you might not want people to know that you are in the vicinity in that part of the world.