Yes.
As per AA 50 Rulebook:
"Phase 5: Noncombat Move
Sea Units: Sea units can move through any friendly sea zone. They cannot move through hostile sea zones."
“Sea Zones: Sea zones are either friendly or hostile. Friendly sea zones contain no enemy surface warships. Hostile sea zones contain enemy surface warships.”
Seems like you should be fine. SZ12 is not a hostile sea zone because it has no enemy ships in it and your bombardment does not make it a hostile zone so you should be good to move the destroyer anywhere you please. Intuitively, since there is no real “battle” taking place at sea, the ships would not have to be in formation and the destroyer may never even come in contact with the other ships. It would not need to be present for their bombardment so it should be free to travel wherever it is directed.
Hope that helps.