If I'm Magic/Pelinka, I would pay whatever the Lakers can for Derrick Rose for a one year deal. It's a low risk, high reward move for a 28 year old former MVP with plenty of athleticism left. The signing doesn't tie up any cap space for 2018. But most importantly in the zero sum game between the Cavs and the Lakers in the chase for LeBron, it weakens the Cavs this season and makes it even more unlikely that the Cavs can field a competitive team against the Warriors. The Cavs will have one more potential big offseason move fall apart at the last second, thereby casting further doubt on the Cavs front office (or lack thereof). Ultimately it opens the door up just a little bit further for a LeBron exit, while simultaneously demonstrating that the Lakers have a competent front office with a plan and a direction.
On the other hand Derrick Rose has no real reason to go to the Lakers over the Cavs unless he is really motivated by the extra money. The Cavs give the chance for Rose to show himself off on the biggest stage and to play for a championship. That being said, Rose is the guy who was rumored to be seeking a max contract as recently as a few weeks ago and has made perpelexing comments before about wanting to have enough money for his son. And it cannot be discounted that when he walks into a Cavs meeting, he will be meeting with the likes of general manager Dan Gilbert and a relatively unknown Koby Altman...while in LA he will meet with the well-respected Rob Lowe clone Pelinka and Magic fucking Johnson.