I've been around the world of ruin, talking to everyone who could be an old man, with no leads regarding the emperor's map I have in my inventory. I've completed the event with Gau's father (who seems to be the main 'old man'), and afterward talked to him with every party member, but still haven't triggered any event related to the emperor's map or gotten him to talk about anything other than waffles. Is there anything I'm missing to trigger the event? Is there any way I've missed the window? Potential bug?