Hm, idea.
Aqua's time in the RoD is, as far as we know, not very relevant to the current story. So why not make it relevant to the next saga? Keep her time there a mystery for now and keep on with KH3. Then have BBSv2 happen, revealing her time in the RoD and have whatever it is that was the antagonist in her story set up KH4.
Nomura's good at making excuses when it comes to characters not mentioning things, so he could probably come up with a reason why she doesn't talk about the events in KH3. :3
This would also keep TAV relevant in the next saga.