My big question at the end of it all was: did anyone ever go back and get the dog?!

Well, according to a post on The Returned's subreddit, Victor and Lucie are water sprites, as per french folklore; some of this is signified by water in Camille's grave in S1, how when the returned arrive the water levels in the dam drop, and how the pit is filled with water (ie the returned) at the end (which is how…

Lucky for Adele she ran into the one revenant dressmaker down there.

I'm relieved that they cut right to the chase with Ash & Amanda. I figured the circumstances they were in were enough to make her realize "Yeah, this is the guy" heh.