Eddie, yes, I can understand Spanish and perhaps the video is of such resolution that we cannot see the rocks, but
one would think such a barrage would be visible on the video near the agent. I see no such stones, but:
I don't think so, necessarily. In the video, people's heads are about the smallest objects one can make out. You can see the agent's arm extended, but I for one can't make out his gun or hand. I would surmise that rocks being thrown would be about fist-sized at biggest, so it doesn't surprise me that they're not readily discernible.
And video "enhancement" a la movies/TV is a whole lot of BS, btw. In fact, anything you see being done with a computer can pretty much be discounted as flatly impossible, highly improbable, or greatly exaggerated. That's not to say that computers don't help investigations; they just don't generally do things that make interesting TV.