Gwenaëlle's look is — not quite pitying, if only because it seems unlikely that pity is something that she's readily capable of feeling for anyone. More like a kinder version of impatience with a student continuously looking at the problem backwards, instead of the solution forwards:

“Why would the system for controlling mages require mage consent? Stephen, we're talking about Templars hunting runaways, not checking whether or not the apprentices all really went to bed when they said they did.”