I think DAL GM will be clever enough not to make that known with comments like:
"We're exploring many options right now - if you're interested in trading picks, why not take on Marion's contract and we'll talk"
I think that's entirely a possible scenario.
If Utah and Dallas are discussing a swap of picks, it will be fairly obvious who the Jazz are targeting, or the Jazz would have no need to make such a trade. We can't just take Marion's contract and 'talk'. They'll offer us #13 and Marion for a TPE, if that's allowed. That would likely leave us with both #13 and #14.
Personally, I think Dallas should take Adams or Gobert. Quite frankly, we might want to take Adams or Gobert too.