Answer to question one: If hes A/Ox3 he has the right to refuse. Just be ready to respond to the adress again for a full code in a bit
Answer to question two: Try getting the wife to convince him to go. use any other family members present, ask him if you may take a look at him. if he does use non invasive diagnostic tools only (twelve lead, lung sounds, BP, spo2, and pulse). This sounds to me like a text book case of an MI. If my theory is correct and the twelve lead shows it you can use that as evidence to back up your suggestion to go the hospital
Answer to question 3: yes if he becomes unconscious check for pulse. if none present begin cpr, begin ACLS protocols, and request back up (we call out two additional medics while working a code) , if pulse is found go under implied consent, get a EKG, Iv established, secure airway if compromised, at the very least give Hi-con O2.
Answer to question 4: depends on what the advance directive states.