The total volume of explosives on Kagame's person is not enough to bring down an entire skyscraper. A whole truckload was involved in the 1995 demolition of Oklahoma City's Alfred P. Murrah Building.
At the beginning of the episode after Kiera Cameron walks up the stair in the boat and the camera switches to Kellog at the refrigerator, a microphone is clearly visible for several seconds at the bottom of the screen.
In episode A Test Of Time (S1E5) it is shown that the leader of Liber8 Kagame is shown with his mother pregnant with him and at the same time Alec's stepbrother was around.