Upvote:3
I read through a lot of reviews, and the only thing I could find hinting at any inaccuracy at all was his own narrative voice. It turns out he had a life-long battle with depression (before and after the camp). I'm not sure why that particular reviewer thought that fact ought to have been more obvious from the reading, but they did.*
I can't find any inkling of someone suggesting the basic facts may be off, and several reviewers claiming historical expertise saying they jibe with what they know independently.
So unless something pops up, it seems fair to treat it as historically accurate. Of course there really are no dearth of first-hand accounts floating around, so it would be trivial to insulate yourself from any inaccuracies in one by reading some of the others too.
* I have three such people in my family, an there's only one its really obvious when they are suffering