This Liberian man was a UNIT officer from Liberia. He was given an Osterhagen key and entered Osterhagen Station 4. He was one of the three UNIT soldiers who planned to carry out orders to use the project.
Unlike Martha and Anna Zhou, he refused to reveal his name due to what they were going to do. He waited for Martha Jones to finish her transmission to the Daleks. However, since Martha was teleported away, they could not activate the Osterhagen Project. (DW: Journey's End)