Fuck the family bickering. Confront them asking wtf they are doing to save a human life.
Print this pdf and bring it to the hospital. You may just find a doctor who is willing to try since this is used in other patients on vents.
You want to get NAC (N-acetyl-cysteine) into him ASAP. Don't worry about anything else because NOTHING else matters right at this moment.
Stand strong, be loud and unashamed.