No he doesn't.
If Microsoft are announcing this as an exclusive now, if probably means their money is being used to help fund the game. For a third-party publisher like Square that's not doing so well financially, covering the cost of development up front can be a huge boon, rather than gambling high development budgets on a potentially larger fanbase. Whatever the game goes on to sell, their initial investment for the game has likely been covered by Microsoft's funding.
I very much doubt there is an evil conspiracy here, and I don't think it's stupid financing. AAA development is getting more expensive. You're going to see more examples of platform holders subsidizing and funding third party games as the costs keep going up.
What are you talking about? Square-Enix has been turning a profit and doing fine.