Fire in the hole mission wont end.

Atm i am doing the hero morality mission Fire in the hole, i've attempted the mission three times already and still the same thing. I rescue the guy, the secretary, and the security chief, then i get the take care of Blast furnace objective. Kill him and all of my objectives disappear all it says on the top is REscue all the hostages then deal with blast furnace. I've scoured the WHOLE map at least 20 minutes each time i have done the mission and nothing. There's nothing left to rescue and nothing left to kill. Exit the mission and the mission marker just leads me back inside.

Did you click on Blast Furnace after defeating him?

You should have to defeat him, talk to him and beat the ambushes (repeat 3 times), and then talk to him one last time and then beat Nocturne.

I think the problem is you are completely killing Blast Furnace. He has to survive your initial strike so you can talk to him. Once you do that, the mission continues.