In one of the long Laci threads I remember reading that Scott had told her about the affair and that she was all right with it. Women are never "all right with it" when they find out their husband is cheating on them. They are always upset, unless they are themselves having an affair. I doubt whether Laci was cheating.
My hunch is though, she found out on her own and left the house very upset. I think he talked her into getting into the truck with him. The dog sniffed her trail down a road that was not near the park where Scott claimed she took the dog for a walk as he was leaving that morning.
Thanks. You're right. Nobody in their right mind is 'all right' with that kind of thing.
I think that Scott may be hiding something he desperately doesn't want others to know about.