You can read a news article about the death of Max Mannheimer here: http://www.dw.com/en/holocaust-survivor-max-mannheimer-dies-aged-96/a-35881809
Max Mannheimer is a controversial figure because he wrote a “später Tagebuch,” which is the German term for a diary written later. [später rhymes with later, as in later alligator]
Max Mannheimer wrote about his alleged years in several concentration camps, but he wrote his book many years after the events allegedly happened.
I wrote about Mannheimer in several previous blog posts which you can read at https://furtherglory.wordpress.com/tag/max-mannheimer/
I personally believe that Max Mannheimer is a “liar, liar, pants on fire.” I don’t believe that he was ever in any concentration camp.