French TV is always like that. They just seem to like that side-on angle whenever the ball hits the penalty box (for some reason). They also love their slow-motion clips of players talking/gesticulating/gobbing etc.
Of course he can. If someone gets injured in injury time itself, or if substitutions take place, then the ref has to add on time to take that into account. As the man said, the amount of time displayed is the minimum that will be played.