During his time running the production company Arcwelder Films (which he founded with Martha Adams), Sayenga wrote, directed and produced many more documentaries, including "Spies Above," "Robots Rising," "Explosive Situations," "High Speed Impacts," "Inside the Kill Box" (made on the tenth anniversary of the first Gulf War and featuring interviews with players such as George H. W. Bush and Dick Cheney), and the engineering series "Skyscrapers: Going Up", "Bridges: Reaching Out", and "Tunnels: Digging In". He was also showrunner of "Animal Nightmares", a 13-part series for National Geographic International; and "Microkillers", a mini-series for National Geographic about pandemic diseases that fused fictional scenarios with documentary content.