Sorry if the question has been answered elsewhere. Is it correct to assume that the creator of these coins may have a copy of the secret key? I am not saying that he has a copy or that he intends to use it. I am talking about technical possibility.
A technical possibility? Absolutely.
Casascius has about as good of a reputation in the bitcoin community as anyone can have. He has stated that he absolutely does not maintain records of the private keys. You have to decide for yourself if you trust that claim or not.