Flash8, this youtube clip is full of nonsense, like "they circled the aerodrome 3 times, according to experts to learn local topography and runway track, which they then enter into autopilot". Unfortunately, we have a pair of self-proclaimed experts that run a well-known aviation monthly, and are often invited to TV and newspapers to sell their theories.
One can only wonder how you can learn local topography not seing a thing...
Avegnon - if they had time to dump fuel (which btw, is impossible on T154), they would have time to go to another airport, international aerodromes were only 15-30 minutes flying time away. And there's no information about any engine failure so far. The amateur movie showed a flashing beacon. And they wouldn't fly for 90 minutes with a known failure to end up at an aerodrome below minima, having a possibility to land at their homebase which was cavok. My colleague was working when they departed, and there was nothing unusual.