Just a thought for especially the front mounted camera would a more central mounting point not be better, if the camera is mounted on the nearside it would not record a hit from the offside and vice versa (due to the bodywork blocking the shot, as can be seen in the posted footage.
At work all the on board cameras were always as far as possible centrally mounted .
I made this bracket up for my Innovv front cam...
I can send a basic drawing to anyone who might want to make similar