abusers are very manipulative. If they weren't, do you think people would stay in abusive relationships? Why do they do that? Because of fear but also because they are manipulated and the abuser gets inside their head and makes them completely doubt themselves. Makes them feel there is no other possible life for them. Makes them believe the abuser's version of reality.
You often have children who have a controlling or abusive parent still loving the parent. The need in a child to love the parent can be so strong. Abusive people can use that to really mess up a child. I am not saying he physically abused his daughter, of course I don't know that and I don't mean to imply it, I simply mean the mentality of an abuser and the way they relate to, manipulate and control their family members. They create a different reality for inside the family that the family members come to accept and believe.
Then you possibly have denial. If he is actually this person, if he has actually done all this - what does this say about you? Refusal to accept the reality of it can be about self protection. Your whole life is not a lie. The person you thought you knew is not a lie.
Then there's financial dependence, feeling like you can't make it without their help (which is an attitude that they carefully grow in you). They may make lots of promises to you, the aim of which is to keep you in line, but you may also hold on to those promises as evidence that they do actually love you. I mean, money and inheritance are so often tied up with and confused with love. You see it even on here in threads where people are unhappy about inheritance and it always comes down to feeling like it is directly related to how much they are loved.
It is all so horribly complex and so long term, it's not something that happens overnight. I mean, his wife - he married her quickly then took her away from everyone she knew, then took off for much of the time, leaving her in an unfamiliar place, with no other form of support apart from him, away from everyone she knew. Making her cling to him, rely on him, even be grateful to him for being there, crazy as that sounds - when you have nobody else, you can become so dependent on the person who put you in that situation!! That's where programming someone starts. By the time he brought her back, he had created a person that depended on him and clung to him. Then the daughter, you take a brand new person and you mould them into what you want them to be, if you are that sort of person. The life you grow up with is what you think is normal and it can take a lot for you to step back from that and really understand it differently.
I don't see his wife and child as colluding, or accepting or whatever so much as I see them as his victims also.