Passengers most don't know about "aviate, navigate, communicate" and panic/get furious if they are not informed of what's happening. I guess it's human to want to know what's going on when you're not in control.
I know, from personal experience, that a lot of the charter-pilots going up north are not that fluent in non-aviation-standard english. And I guess it's harder for non native english speaking people to understand bad english with a foreign accent. Maybe the pilot on IWD did explain to the passengers whats going on, but nobody could understand what it meant. This is just speculations.