I only find info about 12 episodes. So I guess we are halfway through season 1?
I get Kobeni´s point. Honestly, she doesn´t know Denji, and sacrificing him seems like the most logical action. And the situation is scary, I mean look, even the guy cracked under the pressure and was considering killing Denji.
I´m really liking Power potentially being able to treat wounds. If she trains that skill she could be a really valuable ally in missions. I don´t think they would kill Aki, atleast not so soon, I hope.
If he would die it would be later, his character is all about the Gun Devil and we haven´t even seen him yet. So it would just be so unsatisfying to have him die now.