My father is a sociopath, as is one nephew. Neither of them has the slightest insight into their own behavior, and while they can identify the very vulnerable as well as those who are similarly disposed to ignore morality and the law, they can't do it simply by watching someone on TV in little bits and pieces.
Some form of interaction is required.
I'm pretty good at sussing out sociopaths, too. I might have been inclined to think there were others in the Anthony family--but after this interview, I don't think George is one. (I also don't think anyone else in the family is involved in Caylee's disappearance.)
I'm not saying your son is flat-out wrong, but I wonder whether he can have the same insight into someone he sees on TV as he has with his sister, who he's known her whole life.
If George is a sociopath, there certainly are no cracks in his veneer. And that is quite rare. We can be fooled by sociopaths, but once we know the truth about them, it's usually quite easy to see. (It's just that we don't expect others to be amoral, and don't tend to look for it.)