Fred mentions early on that Knox screwed up the Trask experiment and she now has to redo the results. It's clear it's uncharacteristic of Knox to be this unreliable and sloppy (something Wes seizes on as a chance to take potshots at his romantic rival). However, with the benefit of hindsight after the next 3 episodes, we know now that Knox and Dr. Sparrow are both followers of the Old One Illyria and are trying to bring her Sarcophagus to Los Angeles — only for it to unexpectedly get stuck in Customs. As Sparrow's co-conspirator, Knox would know that Gunn's mental upload was about to fail and they would have an opening to trick him into releasing the Sarcophagus into W&H custody. So Knox may very well have been distracted by the excitement of knowing he and Sparrow were about to finally get their plan back on track.
