after you have visited the Afterlife, there's no way to get back. There's no dialogue option in talking to Skraelos (sp?) again (nor should there be, since you have done everything in the Afterlife that the game needs).I figured this was going to be a loss without hacking the game in some way - either by travelling to an unreachable map (Afterlife) or editing the event flags. It's not worth it to do that - the experience will be minor considering my Lich with GM Learning is already level 102 with experience to burn because I've run out of money to train her further. I just like having an empty quest book at the end of the game!
Even getting the missing villagers back won't help because the quest has 3 parts to be completed: Jarl places a stone, pole is fixed (done) and find 7 villagers. You need the Jarl as well. Thanks for the offer anyway.
I'll check back through KKC's posts but I think this is a bust - just checking that anyone had discovered a clever workaround.