As the victim had already collapsed, I imagine that the CPS need to ascertain first that the poor man who died did so as a result of the attack and not from, say, natural causes due to a heart problem or some such. Once the post mortem has been conducted and cause of death determined, they can proceed with a charge of murder or stick with attempted murder.

They'll also need to determine the mental state of the accused. I should think he'll be given a full psychiatric assessment and a history of his mental health will be obtained. He sounds very deranged to me.