You and I seem to be thinking on the same lines. I appreciate you pointing out that TH is not a hands on murderer. It could very well be she passed him on to someone else. Kyron could be alive. Below is my earlier post:
My opinion is that Kaine seems to be a husband that his wives know is going to take the children, maybe out of love or maybe for spite. It seems if both wives were so worried about that at one time, then Kaine must throw around the threat - "I'm going to take the kids and there's nothing you can do about it!"
I agree it's no reason for Terri to plan a murder, but maybe it didn't start out as a motive for money, but spite. Was she capable of placing Kyron in harm's way? There's no real logic to get rid of Kyron in a devious fashion...is there?