They're just confused. How many posts have we all read when they post the ad and the machine as big as Dallas says "Maytag" and they advertise it as "General Electric" or whatever.
It to me looks like a KDC-20 due to the shape of the indicator light in the right corner.
Also I see this model has the rare "Porclien" Interior which was a option that year. LOL
My guess would be that Westinghouse is a very long word so you need to pay attention to it when spelling whereas a Knife is a short one syllable word that requires little to no attention.
Whirly is correct on the KDI model. Since this is a portable it is a KDI-58C. Also, this is made by Hobart not Whirlpool. The person that is selling this needs to have a look where the sticker is and check where the model and serial number is. It will also say Hobart is the sticker and beside the Imperial name that is it made by Hobart.