So what 5 countries do sleuths here think are involved, and what do you speculate TPS are looking for? I would guess, Canada, Japan, Israel, USA ( maybe Florida where BS and HS had a condo), and another country that has secret off shore bank accounts. They are likely trying to find some kind of money trail, or possibly looking at phone records, computer use, travel records, and GPS in cars, maybe even GPS in expensive watches, or other tech items, that would reveal connections between different individuals.
I have wondered about the secret surrogate mothers of 3 of the 4 Sherman children, fathered by BS. Could they, or some of their families be involved? What countries do they live in? Now that both BS and HS are dead, might some of the children want to connect with the other side of their blood families, or could they have made contact even before the murders? I would think the desire to at least satisfy curiosity, and meet your biological mother, and maybe other relatives could be quite strong. Going down another rabbit hole, I know, but it is a very complicated case, and it might be good to know if there were connections. I hope TPS has looked into this. IMO