I would guess that is exactly why they made that trade.
I think any Butler trade involving Detroit will need a 4th team. Butler and Beal are close enough to trade by themselves. But Miami doesn't want Beal, so you need the third team. Problem is, Beal has a no trade clause and he isn't waiving it to come to Detroit. Bring in the 4th team, say Milwaukee. Phoenix can't take the Bucks players because they are taking Butler. Miami doesn't want a bunch of extra salary because they are looking for the quick rebuild around Herro and Bam. You have to find somewhere for the Bucks salary to land. Detroit does it for a 1st rounder. Or some other team.