The Return of Maggie Beckett - S5-E9
Other mistake: The group slides to Fresno, where there is a monument to Maggie Beckett and the astronauts that were lost on an Intrepid mission to Mars. On the memorial stone, her name is misspelled as Maggie Becket, not Beckett as everywhere else.
Answer: The show's creator admitted that it was the wrong Arturo.