I don't think there's too much of a chance that he's overdosed. Overdoses typically happen when people aren't careful enough about their dose increases - too much, too quickly - in some way inappropriately. I think her increases have been appropriate - as far as I can see. The one question i have is about the 29th. She didn't reduce his dose after the 30's on the 29th, though. Do you know why? The 30's should bring a dose reduction.
Those low numbers on the night of the 29th are interesting, however. I'd have thought he'd have had a significant bounce from the 30's, but there he is in the 60's the very next cycle. That would suggest that his body is used to low numbers, but where are they? Serryn's idea of testing in the early morning hours (ouch) is a good one. It might reveal something.