This might not be a greeting thing but a special line thing. I had the dialogue about Gale pop up twice at first, once when it felt appropriate and once after reskilling, when it felt out of place. Afterwards her greetings were normal until we met Raphael in front of the Gauntlet. I am currently play as Astarion, so after talking to Raph, everyone gave me their opinion on the scars - apart from Minthara, who started talking about Gale again.