Is it actually illegal to cheat at fishing? Is there some law against it?
Attempted theft by deception is a crime in every jurisdiction (fraud). The DA is correct in bringing charges and this is such a slam-dunk case that I'm sure their attorney will recommend to them that they seek a plea bargain. They got caught red-handed committing a felony and would have no chance in a trial.
Prolly grand larceny, fraud and most definitely, stupidity . . .