How is he supposed to protect himself? Any parent or married person is constantly at the mercy of the family court.
He can get things in writing, keep a diary, record calls, video the inside of his house but these are really nothing more than grabbing himself a lifejacket on the Titanic. It will only help him, perhaps, when the boat has sunk.
3 little kids happiness depends on Gooch not screwing this up, so I would suggest he seriously considers whether trousers, organic carrots and MMR and all the other stuff he has dominated her with over the years, none of which are condemned under pain of moral sin by the Church are worth insisting on, rather than insisting on just the one that is.
This is where rigourism leads. People lose perspective and beat people up over small things, big things, and nothing all with them same force. It is a serious disease of a number of Trads. Their own over-scrupulousness and worry is projected outwardly on the people around them they claim to love, which then has the effect of driving them away.
I have been a Trad for 30+ years and I have seen this story more times than I care to remember. Usually the Father turning some of the children away from Tradition and thus Catholicism altogether.
And Gooch - if you do get divorced, then when your children come to visit and you tell your daughters to wear long skirts and your sons to not eat McDonalds how seriously are they going to take your message? Don't you think they might think, given that they will be spending most of the time with your now ex-wife, "Dad, you are a real asshole, telling me what to eat and how to dress, you couldn't even keep your marriage to Mum together because you insisted on all this kooky stuff". There is almost no chance they will keep their faith because your ex-wife will turn them against it using you as an example of how it makes people crazy and controlling.
Bernie Madoff might have some really great ideas on investment but who is going to believe them, coming from him? His card is marked.
If MMR does cause autism the chances of contracting it are VERY VERY low otherwise science could detect it by backtesting even if the drug companies were trying to hide it. Neither God nor the Church require you to have a PhD or indeed an opinion in biochemistry to be a father and a husband.