Complex sentence: He worked there from 18 August 1942 until 7 June 1943, and told Claude Lanzmann, for Lanzmann's film "Shoah" (1985), that he had seen around 200 trains arrive during those 10 months.
Split into simpler sentences: He worked there from 18 August 1942 until 7 June 1943. He told Claude Lanzmann for the documentary film "Shoah" (1985) that he had seen around 200 trains arrive during those 10 months.