"Excited delirium" is quite clearly a euphemism for "really high on drugs" but it doesn't meet any meaningful standard as a cause of death. If the cops know someone is high, in a state of "excited delirium", there are a number of things they can do. Are they deliberately ignoring signs of overdose? Or perhaps they are avoiding the overdose issue until medial professionals arrive? It is a lousy situation either way. Should their response change if there are public witnesses with cameras? No training can help with that decision.