This is only possible if Nomura wants to hold onto the one game a year motto he's been on.

 

The 13th anniversary of KH is a once in a lifetime occassion and of course it's a big deal pertaining to the series. Now KH3 clearly isn't going to arrive next year, and with Osaka seemingly ready to full throttle hardcore develop this game. However I do think they've been working on DDD HD in secret and that's partially another reason KH3 is still in early gameplay development (no doubt the story concepts and worlds are all sorted out and ready and putting the actual game together is all that's left) I personally think at TGS we will have another small KH3 teaser (this year is all teasers, next year we will see actual trailers and legit gameplay) and DDD HD will be announced. Whether as a Wii U, PS3 or even Vita title (or somehow all, not likely at all though. Would LOVE a crossplay for PS3 and Vita though!) KHDDD remake would be perfect for the 13th anniversary as it's the next best option to KH3 and we all know how story heavy Organization XIII is to the game.

 

Just my thoughts!

Also most likely the port would not be done in-house like the other HD collections. I can see it getting the Type-0 HD treatment and getting outsourced while being overseen by Nomura or Yasue.