It seems both August and Gold do have a common goal and that is for Emma to believe. August seems indebted to Gold because the fear of death makes people desperate and Gold does have a knack for identifying a desperate soul.
Good point. August’s goal is quite clear. He needs Emma’s magic to heal him. But Mr. Gold…not so much. I can only speculate that he wants the curse to broken so he can leave Storybrooke look for his son.