Glad you made it. But I would definitely get checked out for other than AMS: 4 days acclimation, sleeping for 12 hours, no headache, no nausea, I would say something else was probably going on. Lethargy and disorientation are typical of hypothermia, but nothing else points to that. Harvey?
HACE is the at the far end of the continuum of AMS and can occur even without typical AMS symptoms. Often, the patient appears just a bit goofy-worn out-stumbling around, and he and others around him might overlook the big picture. Fortunately in this case, the ranger did not.
This is from the original 1991 Lake Louise Consensus that is still in use. Notice the last sentence.
[HACE] Can be considered "end stage" or severe AMS. In the setting of a recent gain in altitude, either:
- the presence of a change in mental status and/or ataxia in a person with AMS
- or, the presence of both mental status changes and ataxia in a person without AMS Altitude Illness Lake Louise 
