There's a period of about 1 month per year in which Lower Guk mobs are advanced to seventies. This would make obtaining the Ink of the Dark difficult for a 50th level Enchanter who is just starting his epic.
Difficult, but not impossible, with a few high-powered friends, at least one of which can charm.
If your friends can clear the way and cause a Ghoul Scribe to pop, and there is a high level Enchanter, Bard or a Necromancer who can charm him for you, you can still give the charmed Ghoul the vial. Evidently, it doesn't matter who charms him. Just that he is charmed.
I did this just today and a Bard charmed him for me.