I find it odd that none of the psychopomps have options to travel the planes. Even the higher level creatures do not have Plane Shift as a spell or power. Does anyone know of other options that one of those creatures could use (other than gates) to reach the Prime Material Plan and then return to the Boneyard?
I don't know if this is for *all* psychopomps, but I think the lore answer for how most pyschocomps get to and fro the realm of the living is by using the hidden and winding Dead Roads.