When the French Presidente enters the war room, one man in a suit is seen getting ready to sit down, pulling out his chair. A moment later he's back to standing, talking to another character.
At the station Vincent and Zara discuss about how DCX-Capital financed Jacob's operation. But, it is not shown anywhere in the story how they came to know about this information.
Once they knew the bomb had a mobile phone as a trigger they could have just jammed it or ordered the network shut down in the area.
However, they had no way of knowing whether or not there was a fail-safe, e.g., to detonate the bomb automatically if the network signal were lost.
When Zara is driving in a straight line through the streets of Paris, her hands on the steering wheel keep moving slightly up and down. This is an old-fashioned and unrealistic trope from movies and TV series of the past,
which was the conventional way to display the fact that the character was driving.
The financial plot would not work. Stock markets would be closed as soon as the news was released (if not before). Also anyone found to have made significant shorts before the attack would be investigated and their positions frozen.