How did you protect your gear?
Seems like there would be a lot of mist if you got close to the water?
My understanding is that the Brazil side is for the panoramic shots while on the Argentine side, there are boats that take you right up to the water and there are also catwalks by the water.
On the boats, they give you plastic bags to keep your belongings dry. But that's not going to allow you to shoot much. Maybe best not to take the camera on the boats or avoid the boat trips altogether?