I think it is important to understand all the possible motives of the events that happened, and distinguish facts from ideas, emotions and what each of us believes.
I see the point in mentioning CV's and LV's mutual business account. It's a fact that LV has taken the money out of it and was at least authorized by CV to do so, for she had the access and authority, as I understand it's an established fact (based on the absence of prosecution?). It's also a fact, that she and CV had mutual income earned during the marriage, according to the law, because they were not separated. So what that says to me is that it is possible (not that it's a fact) that when LV was taking money without CV's permission from the account, she maybe believed that it was her right to do so.
The other question is why would she think so - is that because she was so evil, or mentally sick, was it a plan or not, - all these are our guesses based on the other facts that we can see at the moment.
I personally believe that the sick mind can justify/rationalize different actions to itself and to others who are eager to believe those are right and correct because it fits their past beliefs. In my opinion this is what we hear from Cox's family. For me, it's important to see all possible influences and actions to make a complete picture.
I don't think though that CV's business partners could have any possible role in threats to kids or whatever. I don't think this can be any working hypothesis
based on all the information and evidences we know up till now (I mean statements from all related to LV parties about Kay's threats, mentioning of "custody issues" etc).