Granger is an expiring contract and expiring deals don't have the same value they once did in the pre-2011 CBA era.
I think Indiana is content with him playing out the season next year and getting that cap room. Right now, Indiana is at $48 million in committed salary for next season. Assuming they re-sign David West to another contract similar to the one in 2011 (2 years $20 million), they'll be right at or right below the salary cap... around $58 million.
Pretty much, once Granger expires... Paul George will be making the same amount of cash. Indiana is in great position to add a couple more pieces especially a true PG.