I love the contrast between Opera and Kalego's reaction to the situation compared to Clara and Ameri. Opera and Kalego wish to protect Iruma and seeing him get hurt hurts them too. On the other hand Clara and Ameri want to support Iruma with all they can.
Sullivan is in the middle between them. As Iruma's grandfather he wants to both protect him and support him. In this scenario he decided to support Iruma because he knows that trying to keep him safe now won't keep him safe in the long run. Iruma would've lost the pure confidence, arrogance and selfishness in his own desires. That would've only hindered him in his role as the boss.