This is directly relevant to this board, as it is clearly the source.
http://www.gamefaqs.com/boards/genmessage.php?board=946308&topic=49132526
Summary: A few kids attempting to twist meanings in their own way that the NOK Mew is legit in the English copy of the game, apparently, they have selective hearing too.
Oh and a few trolls here are there, however, those are common occurrence on GFAQS.
Discuss on how the database may want to inform of people of errors such as the above, as the database is unmatched in being the unofficial official location of all legit collection of event Pokemon.
Preferably some input from moderators on what to do, as they do maintain and will be the ones to place the disclaimers.