You have to keep the gun on the balcony with Kurtz. Then, if the siege goes badly, you have the option of ordering Kurtz to open fire, even though it means he’s likely to hit some of your own people. If you do that, Sam gets hit a few times and badly injured.
Also, please could we try to keep discussion of the first game to this thread - “Relics of the Lost Age” Post-Release Discussion Thread - Hosted Games - Choice of Games Forum - and keep this one, as much as possible, for discussion of the sequel? Thanks everyone!