Square Enix never said anything about this!
It seems that Tri-Ace staff were involved with the development of Final Fantasy XIII-2. Tri-Ace's Yuichiro Kitao sent out a tweet that said that you might even see him in the staff credits. Tri-Ace pitched in on XIII-2's programming, design and artwork, he says.
I'd like to imagine Tri-Ace looking over Square Enix's shoulders during the creation process, pointing out the silly stuff that wouldn't work well in an RPG. I'm looking forward to seeing the results of their teamwork next month when Final Fantasy XIII-2 will finally be available.
Tri-Ace Helped Out With Final Fantasy XIII-2 [Siliconera]
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11:00 AM on 01.21.2015