None of the TV's shown being developed have a yoke. While a cathode ray tube is essential, of course, without the yoke all you'll have is a dot in the center of the screen.
A patent application for Zworkyn is shown dated 12/29/23, and for Farnsworth dated 1/7/27. The narrator says this is 4 years later. It is, in fact, barely more than a week over 3 years later.