A bit different than in LN I see. In the LN, Hugo would be treated very kindly by the guards and even moved to a room usually used for aristocrat prisoner. Additionally, he should have already worn his battlesuit Noel gifted him some days ago, which explained why he's not hurt despite his power sealed and a bomb defused near him.
Fun fact: Other prisoners actually died from the attack, which Leon should have mentioned and is one of the reasons why he refrained from pressing the button. Also, yes Noel did gift him the battlesuit not just as a gift but also because he knew about the upcoming assassins.