DS3 does unlock, I've got (most of) my palettes on monitor 2.

Make sure DS3 is maximised to one of your monitors, then drag each palette INTO the model window (ie the one with Victoria or Aiko in). It will then unattach, and you can drag it onto your second monitor. Daz will remember palette positions in each view (load/pose/render), so no need to do this every time.