What I haven't heard is "Why"? Sure he was seekign refugee status, but what exactly was stopping him from using his own identity?
Well, the whole reason for seeking refugee status in another country is to escape from persecution from one's home country (usually from a government or from a military group). Chances are he's already in some type of trouble with the Hong Kong/Chinese authorities, which likely means that his identity has been given to any port of exit that he might use to flee the country. If he had used his own identity, the airport authorities would have gotten an alert as soon as his name was input into their computers, which would then alert their security (as well as police/military/government forces) to the fact that he was trying to escape. He then would have been taken into custody, which likely would have ended up being bad for him.
Of course, it wouldn't surprise me if we in the west never get/hear an explanation as to why he was trying to flee China. At most, we'll probably just get some government stooge making a statement about the kid being part of some sort of revolutionary group and/or that he was trying to incite riots or something.