Complex sentence: Harvey helped the choreographer Jens Keith escape to Switzerland; this led to her interrogation by the Gestapo, after which she left Germany, without her real-estate fortune, which was confiscated by the Nazis.
Split into simpler sentences: Harvey helped the choreographer Jens Keith escape to Switzerland; this led to her interrogation by the Gestapo. Afterwards, she decided to leave Germany, one reason being the loss of her real-estate fortune, which was confiscated by the Nazis.