No, in her vision, he fell on some sharp rocks (you know, the kind typically at or near the bottom of a waterfall).  The ones in my imagination are jutting out about halfway down the waterfall, along the side of it (not actually in the main falls, but close enough to be surrounded by mist that the top of the waterfall might be slippery).  Again, I tried to write it so he doesn't have to be at a waterfall. Her vision could be fake if you don't think it fits his character.