The reason why Zhao Yu suspected his father-in-law was that it was Miao kun who had told him the secret operation plan of pretending to be an American agent to deceive amiola!
That night, in the Presidential Suite, Miao kun not only opened red wine for Zhao Yu and the others, but also explained the plan to Zhao Yu.
So, when the plan went awry, and amiola was suddenly kidnapped by a group of people, Zhao Yu was sure that someone had leaked the news.
When Zhao Yu saw from the helicopter that it wasn't an American agent who had kidnapped Aurora, he naturally thought that his father-in-law, Miao kun, might have been the one behind all this.
If they kidnapped ah melaura halfway, then...It would be equivalent to leaving the Korean and American forces behind, leaving the clues to Xi Wei's treasure firmly in their hands.
Even though he saw you SUFU appear later, this thought did not disappear. He still suspected that Miao kun had arranged for you SUFU to appear.