Dave is our resident Statistician, but a sample of 2 is kind of 'tight' to
posit 'too much of a coincidence' on much statistical.
 I'm also not sure what a 'borderline' anything is-> "He's a borderline
painter, he just hasn't perfected it yet."     If the Doctor has done tests
and measured seizure activity, then he currently has seizures.  He might
outgrow them, depending on the type and his development,  or he might not.

   Two things came to mind reading above.   Less obvious might be that some
of us are sensitive to odours and aromas that can bring on the *aura of a
seizure start.   There could have been things in the air that he's sensitive
to, that he doesn't have where he lives (Florida).   Unless it was something
someone else noticed or was 'looking for' when those happened, none of the
rest of you might have noticed those.  Example, are any of the places you
went near those 'Sulphur Hot Springs' like further north in Yellowstone or
British Columbia?  Those hot pools have a profound eggy/sulphur aroma
because of the chemicals in the water coming to the surface, but would be
noticeable to others too.

  Second item, that you might not have searched on, is that I had a period
where I was sensitive to changes in *Air Pressure (Barometric pressure), and
was more prone to a Complex Partial seizure (my type) as the air pressure
fell sharply (usually ahead of a rain or snow storm).   The 'high altitude'
you searched on above, would also be a source of 'low air pressure' which
could affect blood pressure because of expanding blood vessels, and possibly
some types of seizures.  But you might get a few more 'hits' looking at any
posts about 'barometric pressure' or 'air pressure' and 'seizures' (each),
rather than searching on Altitude and Seizures.
  We had one of two threads here last 2 years, but except for my initial
requests whether anyone else had been sensitive to that, I don't recall
there being a lot of others responding at that time.  (I was about to fly to
Hawaii (total 4 flights) and was concerned whether Air Pressure changes
during the Flight or on Arrival might affect my Complex Partial seizures --  
they didn't in my case when done.)

 The 'air pressure' symptoms I had only took place over about 12-18 months,
then they left and have never returned.   I get a 'mild discomfort' if a
rain storm is approaching (like now),  but not the extreme headaches I had
in 1998-2000.  I attribute this feeling to the effect of Air Pressure
falling as the storm front is approaching, on blood vessels or blood
pressure changes while it's happening.
  Does he ever get 'unexplained headaches' now that he's back in Florida?
Did he have those before if he does -- i.e. 2-4 years ago, or were any
recent?

  Hey, some of us can be just as accurate as those Satellite Photos,
although only 2-4 hours ahead of most storm fronts.  :-<   G./