If it doesn't work out, they won't pick up Stephenson's option year but they still benefit by dumping Hawes (saves 11.7 mil over two years).
Not only that, but if he doesn't work out, they can trade his waive-able 9M contract next summer for an asset to some team looking to dump salary, and being capped out, they had few options for picking up talent. This gives them another one.
There's some risk picking up a headcase, but salary-wise, this is a good move by the Clips, and if he does work out, he's a better than average player.