I don't think they're going to go back and save Adam. That storyline was years ago, back at the end of season 5, and he only got one mention since (unless he's been mentioned in season 10 or 11, I haven't seen those yet). I think the writers might have even forgotten his existence. He was a plot device, essentially, he served his purpose and got dropped.
Also, the characters were saying that Sam might not be able to cope with regaining his soul, and that was after only a year and a half in the Cage. Adam would be in a much worse state by now. If they did somehow save him, he'd probably be mad or completely destroyed.
posted over a year ago
I agree Adam's body would be destroyed as it was in a state of decay after Lucifer took it over
