I'm doubtful of that. People hold those first 4 years (2006-2010) against Nomura, but you can't really do that, Square had him working on multiple other games during that timeframe (including directing all of the KH handheld games) and they were also waiting on technology to catch up to his plan for the game. Fact is, by 2010 he had finished the story and character designs, and by the time the 2011 trailer released the game was finally in active development and 25% completed with a scheduled release on PS3 in 2014. We would have long since already gotten Nomura's Versus 13 had Yoichi Wada not made the decision to turn it into 15 and restart development for PS4/XB1. Now, the main difference is, Nomura's 13 was seemingly intended to have sequels, so we might still be waiting on the 2nd game in the series, since KH3 probably would have been prioritized first.
The fact that you have to rely on all these bits of hearsay and empty assurances that they had a plan, doesn't help convince me they were actually going anywhere. Really only hammers home the point, and helps me understand why Square Enix felt they had no choice but to hand it to a different lead and team.
If Nomura cared enough and actually had a clue where he was going with the project, he probably could've convinced them otherwise. But someone who bursts into work one morning with an epiphany of turning their JRPG into a musical, probably doesn't lend much hope to investors.