Wednesday's face was always pure from emotions. It wasn't that the boy couldn't feel emotion, instead he was the only person in the castle who was perhaps the most raw when it comes to showing his expression. His master had told him ever since his childhood how his purity and innocence could be a double edged sword. Sometimes this can make him pure and innocent while other times that purity might seem like a sinister malice as he had done it thinking that was the only right approach.
However the boy wasn't particularly clever enough to understand what his master had said. If there was one thing he was good at that was not thinking much and let his own emotions judge whether it's right or wrong, not knowing that was what Magnus had told him to be careful of.
In his slow mind, he could tell that Destiny had done something bad and how she is the villain to this all.