Actually, he can control the franchises, and manufacture the item so it is sealed, and so it is kept under control of the franchisees. Then he only has to trust the franchisees, and can write huge monetary penalties into the contracts for disclosure.
FOod companies manage to hide their trade secrets of things like what is in secret sauce or the formulas for drinks, even though all of us have a Coke in the frig, and the products are manufactured all over the world.
Not saying that this explains anything in this case, just that in theory if you have an idea that is extremely obvious, and maybe even DONE already by someone else who just didn’t figure out it’s value, you can make a living using trade secrets and hiding the particulars.
The Coca Cola formula has been successfully hidden for many years through the simple expedient of putting it into the hands of a trusted contractor ~ unbeknownst to the Board of the Directors or management.