That's true and i don't think the sheriff was saying he wanted to "make up laws on the spot", just that he wanted to work with the DA and the Feds to see what laws are already on the book that might be applicable here in order to move it up from a misdemeanor to something more appropriate (not just to protect local authorities from public pressure but also to serve as a deterrent to other wackos who would think "gee, do something like this and all i have to worry about is a lousy misdemeanor!? haha, cool!"). Given the unusual nature of this case, i think it is warranted to take such a step.
I think civil damages are going to be more onerous than any criminal penalty. Plus there will be the public shame. Any publicity bid has backfired in his face knowing that he caused rescuers to go on a dangerous wild goose chase.