But you are correct, if it was in fact AI, showing how he (or someone else) made it at the time would certainly help get him off the hook.
Guy could've probably picked a better place to base jump anyway, national parks are notorious for having a billion laws that don't really exist anywhere else.
You can't even take your cat white river rafting on the grand canyon >:( https://www.law.cornell.edu/cfr/text/36/7.4
What are the chances that rule came about because of a dead/lost pet or because of some wildlife that was eaten? I'm 50/50 it was either.
I've done Grand Canyon whitewater (part in an OC1, part in a raft). A law against animal cruelty isn't a bad thing.