If the pc is absolved by a dark gods power then why would'nt the soul go into captivity in a version or the dark gods domain. That's what keeps the soul away that long. they are imprisioned.
This alows a interesting "medaphore" session as the pc's fight and try to escape this new hell.(where they cant die beacuse they are already dead. But pain on the other hand......)
Now , if only all the pc's, or all but 1, accidentily got absolved then the party would be together.....
Isint it convienent that the death of the final devote sets off a dark pack/contingency of retribution on behalf of the dark god affecting all within the temple for destroying his cult as a final act. This would be a ritualized spell set up long ago with the formation of the cult of course and of enough lvl to be aproprate.
just an idea