I'm on the fence about Stan at the end. He seemed too overly happy when he was telling Philip about Paige and his son, as if to rub it in his face. I know as a parent of both a boy and a girl, there are differences about how we view each gender 'hooking up'; boys get a pat on the back and girls get a stern warning, but it seemed like he was sort of bragging to Philip about his son 'getting it on' with Paige, which to most fathers of that girl, would not really be a high five moment. I conclude from that, that William may have told Stan who they were and this was sort of his way of sticking it to Philip.
On the other side of it, if William didn't actually tell him the names of the two operatives, he definately planted the seeds - calling them the perfect family, and eventually Stan being the smart guy he is, will start putting the pieces together.