The scientists at Der Riese including Ludvig Maxis and Edward Richtofen were trying to find out what had happened to their test subjects.
Some scientists at Der Riese got their hands on some zombies to test on. The scientists tested the teleporteres on SS Honor Guard soldiers, however, they didn't appear at that other end and some DID appear where they were supposed to, but were reverted to a zombie-like state. The story starts with Der Riese (which is 'The Giant' in English) where German scientists are developing teleportation devices to help win World War 2.