Continuity mistake: The clock on Danielle's hospital room wall reads 11:40 a.m. when she's brought in. Seconds later when the nurse leads Rembrandt to a bed because he thinks he's going to give blood the clock on that wall reads 2:30 p.m.
Continuity mistake: When Quinn has the real Duke's sword, he's pointing it towards the Duke. When the Duke tells his story, Quinn is dropping the sword down to his side. In the next shot it's back up pointing at the Duke.
Answer: The show's creator admitted that it was the wrong Arturo.