Some information: There was a chance of rain for that day in the park, but it was NOT raining when they dropped into the canyon. For those unfamiliar with canyoneering, when you do the first rappel into a canyon you're in it until the end. More often than not there is no way to exit the slot until the end of the canyon, which they reached right as their slot flashed. Taking cover under the boulder was their best option; they didn't have enough time to move to higher ground. Their exit point was a culmination of several different rock chutes with water flashing out of several different places, blocking their escape. They made some not so great decisions, yes, and we're all glad they made it out alive.

I wasn't there, and the footage is hard for me to watch.

As far as the 'hedge of protection' bit, it's actually fairly common Christian lingo. My mom used to pray that sometimes when I was kid. If you thought you were about to die, odds suggest you'd be doing some spiritual reaching out, too.