You know, some years back......the very very dead Dr. Rolf suddenly was Alive and well, in the DiMera mansion (I think John was living there at the time, robo John as some called him, as he thought then he was a DiMera)
Sami's jaw dropped, as she said, "but you are dead".....and Rolf replied "It didn't take".
The reply is infamous.......and I would definitely take it said by Jack, if the writers are unable to figure out a way to bring him back, since we never saw him die, or his body, nor did anyone in the family, since Cameron was the one who made the I.D.
As to Will, Gad, they did such a good job of killing him, dragging his body to his apartment, having it lay there for several house, etc. I honestly don't know how, but then...just remember Rolf....to whom the same thing was done. In fact, his dead boy was even blown to pieces. Never say never!