Was it espionage? I'm not sure about the wording of the law. All the article says is that they kept tabs on anti-Castro groups in Florida, with no claim that they obtained or sent any secrets. Every country, every embassy, has folks who do that sort of thing, and as far as I know it's legal, as long as you register as someone who's working for a foreign government.
How about MURDER charges?
Don't you think the info passed to the commie scum in Cuba led to the imprisonment and deaths of Castro protesters that had contact with the immigrant community here!!??