So here is what I could come up with.
Miami - Harris, future 2nd (from Bos)
Philly - Lowry, Tucker, future 2nd (from Bos)
Boston - Robinson, Thybulle, 23
So Boston absorbs Robinson into the Fournier TPE, Thybulle into a smaller TPE, and gets 23 for 2 future 2nd's. Miami gets out of Lowry and Robinson while getting a solid player in Harris. Philly gets out of Harris, but takes on Lowry and gets Tucker at the expense of Thybulle and 23.
Edit: And I totally get 3-team trades aren't common, especially for 3 contenders to all trade with each other, but I do think it is a trade that makes a fair amount of sense for all 3 teams.