The fact that they HAVEN'T said anything is enough, if there was anything to say we would have heard it, their silence speaks for itself. Game companies don't make announcements on what they're NOT going to do, I don't here Nintendo denouncing a sequel to the 80's NES game "Wrecking Crew" THAT MUST MEAN IT'S COMING OUT NEXT WEEK! No, it doesn't work like that. The fact that Square Enix had the largest opportunity of the year to say something regarding KH2:FM outside of Japan, and they chose to say NOTHING is proof enough that there is indeed nothing to say.
E3 is the largest video game related convention outside of Japan, E3 was Square Enix's chance to tell anyone outside of Japan what they felt needed to be said, and they said nothing. If Square Enix had an international release of the game planned, they would have stated so at one of the only opportunities of the year in which they have to make such an announcement, when the American audiences are watching and listening. They said nothing, they've said nothing for the past 6 months, they've said "it's not in the cards", it's simply not happening
Square Enix is notorious for being completely steadfast in keeping their Region-Specific Special Edition games in those regions only, KH2: Final Mix is no different. They want it in Japan, it will stay in Japan. We're not being negative, we're being realistic, we're not getting our hopes on something that all odds point to it not happening, and we're not going to waste hope on the hopeless. I'm telling people to accept that it's not going to happen, because I was there to see people waste years hoping that Kingdom Hearts 1: Final Mix would leave Japan
And as HadeDragon touched upon regarding hope at TGS:
It is highly unlikely that they would be announcements about a North American and Europe/Australian release of the game at a Japanese event, the Japanese do not care about what games are coming over to us. If there is to be an announcement about a NA/PAL release of the game, it would be at an English gaming event, in other words, E3 was your last hope.
The Tokyo Game Show is a Japanese gaming event, with Japanese fans, taking place in Tokyo, which just so happens to be the capital of Japan. So why would Square Enix of Japan talk about an English release of a game at an event that takes place in Japan, where Japanese fans are attending, in the country of Japan?
Do you want to go to your local game store and hear about what games are coming out in Belgium next week? Or how the French localization of a game is coming along? Or how much that game costs in Australians Dollars? Or what games are topping the charts in China? No, of course you don't, and neither does Japan
It's better accept something as hopeless and move on (perhaps to be happily surprised to be proven wrong if what you thought hopeless turns out to happen), then to keep your hopes up and assure yourself that it's going to happen, only to have your hopes dashed and stomped on realizing you wasted months/years anticipating something that you should have accepted was not going to happen.