You can try to explain, reason, justify, and convince from now until doomsday, but it will never make this piece into something it is not.
I understand the need to feel as though you have found something special. And, once you have convinced yourself that your "coin" is a genuine rarity, it is almost impossible for your mind to be changed. But, several different knowledgeable people, (and a few actual experts, who have handled genuine examples of these), have informed you of what you really have.
Kellogg & Co. was a respected manufacturer - even receiving the endorsement of Augustus Humbert - and, I believe, would never have released a piece of this inferior quality. I can guarantee you that they would not have released a coin containing half the proper amount of gold, which, in another post, you said your coin has.
Carefully, and without bias, compare your piece with pictures of genuine pieces. Pay particular attention to the hair detail on the obverse. That, in itself, should be enough to convince you that this is not a real coin.
As for your dispute with PCGS, you need to pay them for their opinion and be done with it, in my opinion.