Zeroxal might have used botnet services or be avoiding paying tax, if you think that is the case then you should have reported it to the Austrian* police with any accompanying evidence. That way, a person who is in the correct position of legal authority could have run a sting operation which was signed off by a judge. Amateurs trying to run extortion schemes would likely just become an accomplice to the original crime, regardless of your intentions. Trying to act too clever can be your undoing.