I dropped by on Saturday this past weekend to see what the claim looks like - and I have no idea how to get down to it. The river is running at the bottom of a very steep embankment on the side of a twisty mountain road - though I could find some places to park, I couldn't find one near the claim that looked like it had any access to the river where I wouldn't slip and break something. I won't pretend I looked that thoroughly, as again - it's a twisty mountain road, tricky to drive back-and-forth along it.
The far side of the river has a small level area/bank then it goes quite steeply up the hill/mountains on the other side. If the river rose quickly, you could have a bit of a desperate scramble up a steep hill to try and stay out of the water.
I WOULD go if I could find decent access, but I'd be very cautious. I did have a Very Bad Time on the Kern once doing some recreational floating - the water CAN pull you under, and if you were to trap a foot under a rock in that scenario it would not be good. It was far less accessible than I thought when I looked on a map, though it's a gorgeous spot. The water's not flowing TOO high/fast right now but again, I'd be hesitant to bet on that if there are rains or snows further upstream. I can't say that I really understand this claim - I'd love to hear if/how others have accessed it.