I hate to discredit a good conspiracy theory. But have you ever noticed that the tail of a 747 and A330 are very similar in shape and proportion? In fact quite a few times, from a distance and with the fuselage hidden behind a building, I have mistaken one for the other.
Is it possible someone has simply seen the top half of the tail of a JQ 330 and mistaken it for a 744?
Especially given the lack of photographic evidence of this abomination...