It shouldn't be, not really.

Since the NPC just opens a window. It's not like the NPC you talk to for the sacks, or the one beside it for gear.

Since the scripting is in place, largely it's just a matter of adding a menu item, have it call a choice thing, then point it to PotD or HoH's window script, that the NPC uses.

It could probably be accomplished in less than a day.

That's one reason I posted it here, on the off chance it might get implemented.