Given that I suspect he was relieved that the baby was dead (afterall, he never knew "it" (fatherhood) would be this way)
I remember what it was like before DH and I had kids. We took care of our best friends' 4 month old baby at our house for 24 hours.
I was totally surprised by what it was like to take care of a baby. It was nothing like I had imagined. Of course I realized that when one is responsible for a baby, the baby has to come first.
What I didn't realize was that the baby coming first interfered with everything I had to do. I either had to give up doing something or stop what I was doing to take care of the baby. During that 24 hours, nothing was done completely, except for caring for the baby. I didn't even sleep well or enough that night -- the baby did -- but I was worried that he would stop breathing or something on my watch, so I glued my ear to the monitor, and heaved myself out of bed every 30 minutes or so to check on him.
When I had my own kids, that was frustrating at first, until I got used to it. Mind you, my "first baby" was triplets, so I was a bit busier than most new mothers are, but I think the transition would have been a bit frustrating even if I'd had only one baby at a time.
So, I don't think that just because a new father says he didn't know having a baby would be like it is means that he didn't want and love the baby. It just means that he is still getting used to this major change in his life. I'd wager that a lot of people, if not most, are centered on themselves until they have a child. It can be difficult to adjust to putting a child first, and it can be wearisome at times, even for those who have done it for years.
Also, since he is the father, he was probably having to get used to changes in his wife, too. I am sorry for him that the changes in his wife turned out to be such horrific ones. Nobody would expect that, I think.
I am not saying the husband is innocent -- I am saying that he may very well be.