This is for anyone curious of the coming chapters, this is from the novel, pardon if its a bit confusing as i am typing this out of my memory only...
Spoiler!
MC will actually reveal how he manipulate aura by using the technique from the murim world and dragged down the name of Alexander as the pioneer of aura and shocked everyone who attended the exhibition even Alexander himself. But Mc was not worried to share this cause its only the basic he thought, how to improve it or get stronger depends on who is learning and training but for others it was already revolutionary idea. Now regarding the spies ..they were some who already admitted to be spy but still betrayed Dmitry so they were captured and tortured while those who stayed and later admitted the truth was helped to save their families from Kronos empire and sworn loyalty to Dmitry.