I'm finding the same, it's going in circles and people who don't live in the area (or aren't familiar with rural areas with limited cell service) have no clue what it's like. They just don't understand how connected the communities are along the highway are, how often many of us travel both highways, how familiar we all are with them and people along the way, how travelers connect on the highway, etc. All it takes is a couple signs posted that afternoon and word would have spread that day.
To me it doesn't matter about the terminology of the warning when it did come out or how much Canadians understand said terminology. My point is that it came out 36 hours too late. People on that highway that day and along the highway (us in the Yukon) deserved to know about the murders (or suspicious, deaths, whatever you want to call it I don't care), THAT DAY. If it's possible that there are killers driving along the highway, then alert people ASAP.