We just talked about a situation where someone has to remain on the scene and not a situation where someone could call anonymously, leave the scene and make sure that help comes. That person would no longer be on the scene when help arrives. This is more about a situation where someone would help an individual while waiting for professional help to arrive. Currently, someone can call and leave the scene, with help arriving after they're gone.
I see that there is an issue with that in Vancouver, especially when it comes to police involvement. I was not aware of this, but I just heard about it. I don't know if the situation is the same across Canada.