The comment can be found on YouTube, if you just copy&paste the comment into google, you will find the video & user comment below. On the users profile it says this guy is a russian singer, and he seems to try to advertise himself just like LM did.
BTW I found a site where LM might have posted after Lin Juns murder.
Its an article about Karla Homolka on crime.about.com. The second comment (from 2008) seems to be him, talking about KH being married to LM.
Then, a comment from 2011 says LM is behind the kitten killings. Then, a user with the name Karla Homolka makes some comments (not sure if LM or just some other troll). Anyway, it gets interesting with a comment from January 2012, username "Karla Magnotta", pretending to be Karla. In April, 2012 there is another comment from Karla Magnotta, saying LM would be a big star. May 30th, a user comment ("Connie") that LM is wanted for the murder of Lin Jun. June 1st, "Karla Homolka" responds to Connie that they would be living together in the USA and dont care about Montreal cops.
This is nothing of importance, but its interesting, I believe this was really him, commenting while on the run.
Article can be found when googling "karla Homolka crime.about.com".