The only explanation it would require is that she survived. We don't know where in her body Silvio shot her. We don't see that. TV has given us some bizarre plotlines (how about Bobby Ewing's dream); Ade's return would not even reach that threshhold. I can see a teaser during the final seconds of the final episode of season 6 as the camera pans by a hospital intensive care unit where we see a blonde women lying in a bed hooked up to all kinds of tubes and machines. Is it Ade or isn't it?

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
"Instagram is Twitter for people who can't read."