It's good that you checked it so accurately, but if what Rosbone said is true we cannot fully trust the FOV. There seem to be some differences of ~2 meters if I would need to guess.
A_E said they double checked the ML replays with the live casts and found no difference in the fog of war. I'll take that over Rosbone arbitrarily declaring how consistent fog of war is off the top of his head.
As for the gif Rosbone posted, it seems like something else is going on. 1 frame is not enough to explain about 4m of extra LoS gained in the 2nd clip. There's something else involved.