Ultraman Decker S01 E17 Investigation from the Past

Captain Murahoshi is under investigation?! The Director of the TPU's Internal Affairs, Agent Nigel, suspects Captain and Agams might be working together. Kanata is shocked, but Nigel shows no mercy and looks for any suspicious acitivity from Murahoshi. Why doesn't Nigel trust Murahoshi? Is there any way to clear Captain's name?!