There seems to be a bug with the quest "Tree's Company" that I can't get around. The quest giver (Admiral Odesyus) permanently has the gold question mark symbol above him showing quest complete. However, I have not finished the quest, and cannot make progress in it either. Even if I abandon the quest the symbol does not go away. To complete the quest I require the item "Tree Disguise Kit", however I am not receiving this item on the start of the quest. This makes the quest unbeatable.
Another player I am playing with is also experiencing this issue.