She's trying to pretend she doesn't remember him (look at her expression: she's looking away, clearing her throat, stuttering over her first word), but she accidentally shows that to be a lie by using his full name when he only gave her his last.
Francois has changed over time, but not because of the granny/man. It's been said before in the series and it says it again right on the last page: different eyes see different things. Miko's dad saw the spirit as a granny; Miko sees it as a dude with a sickle. It's the same spirit, the only...