So how can we examine his rightness or wrongness?

We can say that Mrs Marlow is there, making the parenting decisions that need to be made - which we, with the benefit of omniscent observers, get to criticise. Mr Marlow is simply absent, making (as far as we can see) no parenting decisions at all. Parenting decisions have to be made - and we can (or we could, except that the cultural paradigm does not support this) examine the utter wrongness of Mr Marlow simply escaping any responsibility for making parenting decisions. Which lack of responsibility is... unexamined.