Ahoy , 
 I just heard about Mollath the first time today from a Facebook posting, and find the situation very interesting. Thank you for putting so much effort into spreading the word to the English wikipedia. You mentioned German wikipedia would autoblock someone if they quoted someone saying "I'll fuck him up"? But there is the situation with the youtube link. Have you tried using something like youtu.be? 
 I'm pretty certain an article like this would have been marked for speedy deletion on the German wikipedia before anyone had much chance of filling out the article, so I hope this one will turn into a good one. 
 As for a translation of "Ich mach den fertig", said by somebody in an angry mood, and meaning to neutralize somebody, "I'll fuck his shit up" is a bit too strong, and "I'll mess him up" is maybe a bit weak.