He didn't denigrate anyone? He said he loved and respected a dictator, someone who has been pretty cruel to Cubans. So much so that some of them try to float across the ocean on poorly made dinghies, risking getting shot or eaten by sharks. To me that's denigrating the people who have suffered under his rule. Not to mention the fact that Guillen sort of insulted the USA by saying Castro was able to avoid being overthrown/killed despite American efforts. Obviously, that's the less insulting part of the comment, but to say he's not denigrating anyone is incorrect, in my opinion.
I think you will get your wish.