Ur see8ng 8t backwards. There was a loco on both ends of the tra8n. The loco that's pictured next to the truck is the rear 9f the train. See below for diagram
U do realize the loco in th8s pic is the rear loc. The lead8ng one 8s way down the tracks. A congressman even posted a pic of it to twatter I believe. Plus multiple congressman reported 2 abrupt jolts with the first probably being theeng8neer hitting the e-brake. Plus they back tracked to Charlottesville to drop off the gopers so they could board a bus. Watched it happen live