Going to a separate gym, even with a female trainer, is an opportunity to be groomed by other gym rats and/or the female. The whole gym genre is notorious for facilitating stuff not marriage friendly. But you likely know that already since you spend hours (?) there yourself. There have been plenty of instances where female convinced a wife to "join the other team" if you get my drift. If she is spending hours at the gym, she has bonded with who knows who there.we used to go to the same gym, she needs a trainer, and her trainer moved to another gym so she also did.
You have a lot of money, and evidently a lot more on the way. That is a major attraction, especially if your wife has been publicizing the situation.
BTW, is the wife maybe bored with working from home? Something has happened to change ( or maybe expose ) the dynamic in the marriage.
They have joint accounts. Which means if he kicks the bucket she can access all the money they have in emergencies or otherwise. In fact, she could clean him totally out right now from both the business and personal account. He wouldn't even be able to hire an attorney. Worse, if she absconds with the funds from the business, he won't be able to pay the taxes either. I had a friend long ago whose business "partner" pulled everything out of the business account, left the country and my friend with no money and the IRS looking to him for their money. Not a good position to be in. I would have thought a business account would require both signatures to access funds, but what do I know?I think your wife should have some money, for emergencies, in the event of your death. Just to keep things simple until she sorts everything out.
My advice to him would be to get a personal account for himself and put at least as much in it for his own use as they put in her personal account.