Okay. I just watched a youtube tutorial on how to do this....
1) If you need youtube to figure it out, it's obtuse. (85% of the gaming population shouldn't need youtube.... KingsQuest is rolling over in it's grave )
2) If the quest requires a unique object, just tell the player that. Why make it a mystery?
3) If there is an alternate solve, with common objects, just tell the player what to get.... and pickaxe should be included (obviously)
This quest is amazing to me. On many levels. Wow.