Vi is from Rivain, but only lived there until she was about 10 or so until she started a career of piracy. However, she does port in Rivain frequently at Dairsmund ~ and since for most of her adult life she had a penchant for keeping relationships confined to whorehouses, it's likely that they met at some point during his tenure there as long as she was of age ~ even if it was probably strictly a business relationship with a good customer ;)
She also has a boat and takes on passengers - it could be easy enough to say she gave him a lift at one point or another.