If he was put into a cooling protocol, it would be a minimum of 48 hours from protocol initiation before they start weaning his sedation. Further, most cooling protocols include continuous neuromuscular blockade (vecuronium or cisatracurium), to eliminate shivering, so even if he is ready to breathe on his own, the meds prevent him from doing so.
If he is in a cooling protocol, then it wouldn't be too surprising that the family doesn't really have much to share.
Of course the differential is pretty wide here. When seeing him drop, my differential was, spinal cord injury, commotio cordis, pulmonary embolism, or tension pneumothorax or cardiac tamponade, from an earlier hit in the game.
If reports of weaning to 50% oxygen, and mention of positioning to improve lung function, are correct, this suggest that there is a problem with the lungs themselves. Either this is not primarily cardiac, making tension pneumothorax a higher possibility, or, more likely, something like aspiration happened to them during resuscitation attempts.
Too many unknowns, and too little info, but I wouldn't get too nervous unless we haven't heard anything by Thursday afternoon.