"That's pretty smart, Hazama-san..." As he makes a show of being impressed, his mouth even forming a little 'o', Aoba thinks over the situation. A cypher, huh...

"Let's hope it doesn't come to that, at least." A hostage situation is probably one of the worst possible outcomes here. ... Well, if none of them have the cypher, they're worthless as hostages anyway, so 'a hostage situation' isn't even possible to begin with.