Let's ignore all the times in the article the keep saying every claim is "unproven". Let us even never acknowledge the fact you can't patent a list of ingredients and just because you might take someone's ingredients it is technique that is perhaps more important in making a food dish. ( And the good Colonel clearly developed a unique cooking technique by using pressure cookers).
Instead let's focus on Sander's history, he was a Jack of many trades and failed at most. He was running a gas station for that new craze the car. He figured he could make more money from people for gas if his service station was able to offer food which made more people stop at his business. In order to server diners faster he came up with the pressure cooker technique. When the new highway was built in the other side town the station went out of business, again he was broke so in his 50's he grabbed his recipe (refined to taste good for pressure cooker) and the pressure cookers and eventually sold his idea enough times to finally achieve success.
The point being the guy at first was attempting to make a success of his service station so he probably just made the chicken his wife made for Sunday dinner. When he needed to speed up cooking times using pressure cookers he most likely reformulated any spices he was using to taste good under pressure. The recipe was an afterthought that happened to cook chicken quicker in order for more people to stop for food in order for them to buy gas at the station.