To be a criminal you actually need to perform a crime. He did not perform one if I'm reading your post correctly.
Code:
Whoever, under a threat of informing, or as a consideration for not informing ...
demands or receives any money or other valuable thing, shall be fined ...
or imprisoned not more than one year, or both. 18 USC paragraph 873 -
demands or receives any money or other valuable thing, shall be fined ...
or imprisoned not more than one year, or both. 18 USC paragraph 873 -
US law doesn't apply to the whole world btw..
All countries have similar laws about extortion, AFAIK. The word OP used - "criminal" - is therefore adequate.
Since these forums are anonymous, and the admins can't give out personal information, even if they wanted to, good luck
Although I guess boxman90 could be his real name