Sorry, I haven't read all of this thread as it has got too big. To me, the bottom line was that Toby had special needs and they seemed to keep avoiding dealing with that and just making the assumption that "better parenting" was all that was needed, as well as the practical comforts and love etc. A child with SN needs, let's say for the sake of argument, TWICE the amount of parenting than a child with no SN but they are, let's say, TWICE as hard to parent, therefore its a double whammy. The whole situation was tragic, the parents had serious problems, especially the dad, which were probably not their fault but that doesn't help any kids. No amount of improved parenting was going to be enough to deal with his SNs and they needed to get to grips with that asap.
Friends tell me they've had SWs who are obstructive and difficult but we've had wonderful SWs over the years for DS (ASD), some better than others. In fact, we had the same SW as a friend and I thought she was fine and my friend hated her!! I also have a good friend who is a SW is Child Protection who has a child with SN herself and her job is mind blowing.
I thought the "parenting" issue was a bit of a smoke screen and they needed to deal with the SNs of the child.