Austria’s ambassador crawled his way to understanding what the Holocaust means to Jay M. Ipson.Ambassador Christian Prosl, dressed in a dark pinstriped suit, followed the 74-year-old Ipson on all fours through a lightless tunnel in the Virginia Holocaust Museum.They arrived in a tiny, infrared-lit room that re-creates the shelter where Ipson and his family hid under a Lithuanian potato field to escape deportation to Nazi death camps.Prosl came to Richmond yesterday to present an honor that Austria never before had bestowed on an American. He presented Ipson with the Austrian Holocaust Memorial Award, given since 2006 to people who have worked to educate the world in the lessons of the Holocaust.