Yours is a good opinion. Listen to the audio carefully for any video at the time of the blast. There are distinctly two concussions. This is especially noticeable in the video where the officer goes around the corner to his right, walks a block to his car, starts to put on a vest and ... ba boom. Audio experts told me the modulated volume level control may have cut the recording but doubt it could record, cut and continue recording and give the two concussion results. They are looking at the audio traces.