Other mistake: While Cadet Hayes is being interrogated, he says, "I studied the photos of your son's death. They called to me. I don't know why, but it was a message and I listened." Then Scully answers, "And then you killed Agent Doggett's son." This answer is illogical and complete nonsense because the photos of Agent Doggett's son were taken after his death. (00:36:05)Chop Luftmysza
Other mistake: When Doggett starts clawing at the freshly plastered wall, he does so at just below his eye-level and blood starts pouring from the hole he makes. The dead woman inside the wall was stabbed in the lower abdomen; there's no way that blood from the abdominal wound would've seeped through the wall at the level he was digging.