The Cerra trade set the a benchmark for what a reasonable trade looks like for a high draft pick that had (to that point) realised their draft potential but who wanted to go home; basically you get your draft pick back.
I assume Melbourne just went to the draft pick calculator and worked backwards. Pick 13 this year and the same next year doesn’t add up to pick 2. Now they are just playing the hokey-pokey to make up the points.
All of that is reasonable as far as the trade goes; it’s just a lot to handover for one player unless you think they can be an absolute weapon. So, I guess over to JLo?