I think his best chances would have been the earliest possible intervention. If his parents monitored/limited his internet usage as soon as they became aware of the trolling, his life would have been a lot different. They should have got a new, unlisted phone number as soon as they started getting prank calls, and stopped allowing him unlimited, unsupervised access to the internet. I see those early videos of his where he's in his bedroom yelling and flopping around, and I just always wonder "where were his parents at?" Like what were they thinking, they had to have been able to hear this stuff and why did they not go see what was going on? It took Bob to be worried about the house being condemned to step in and tell him to knock his shit off, and that lasted about 10 minutes. They should have taken it as seriously when he was babbling about Clyde Cash and Australian brush fires etc.
Bottom line is that Bob and Barb failed Chris, with a better support system he would have done better. If they would have educated themselves on his condition, listened to Dr recommendations about treatments and followed them. I've always found Chris to be pretty unlikable and never had much sympathy for him, but it is actually sad because so much of this stuff was easily preventable for any two parents with a bit of common sense. That family had their entire lives consumed by internet drama due to the inaction of the parents.