Sounds like he has sleep apnea for sure. But I wouln't think that the rash has anything to do with it.Why don't you try a dermatologist for the rash?
I would like to know what the doctors say. This is strange. Do you pick it up with an apnoa monitor?
he is going to a neurologist and a pulmnologist sometime in Feb. he gets the apena usually when he is asleep or just laying down wide awake. The heart rate alarms would go off when he is asleep. The rash looks kinda like wind burn almost..but, obviously, its not. its all over his face, even the top of his head looks like it..kinda like a sunburn.
Get your son to a specialist urgently. They need to check for seizure activity. Does he have these apnea attacks while he is screaming? Like screaming and then taking a deep breath and not breathing out again? That could explain the rash (little needle pricks under the skin??)