She says pffft your MUM's face will stick that way.
Weeelllll, Maura has never said no to a first date in her life, so if he ever asked she said yes. But if that is Not His Thing, she is also prone to asking, so maybe she asked (super-duper casual, of the "hey, let's grab a drink in Hogsmeade" variety) and they went and he got confused so she got confused and well that didn't really work let's never talk about it again... maybe? OR SOMETHING!