Outside of the immunity to Charm it was still a decent use of an action/ready action.
I think you could rule either way on if the zombies/lich would jump off a cliff after the gem, since the spell mentions that they specifically stare at and approach you (not the gem).
Casting a spell and holding it uses visible components the hobgoblin could react to.
Incite greed also explicitly says that the creature avoids obvious harm while approaching you and does nothing beyond approaching you. If the would always run after the gem (forsaking personal safety to do so), this would be noted in the description.
Outside of the immunity to Charm it was still a decent use of an action/ready action.
I think you could rule either way on if the zombies/lich would jump off a cliff after the gem, since the spell mentions that they specifically stare at and approach you (not the gem).
So you better jump off and cast feather fall.
Casting a spell and holding it uses visible components the hobgoblin could react to.
Incite greed also explicitly says that the creature avoids obvious harm while approaching you and does nothing beyond approaching you. If the would always run after the gem (forsaking personal safety to do so), this would be noted in the description.