A few unanswered questions

1. Why does the one V C guy randomly start shooting at Nick and Mike when they are in the water before they're forced to play Russian Roulette together? and then he just randomly stops shooting??

2. What could be the reasoning for the way Angela acts when Mike asks where Steve is? Is she just traumatized by whats happened to steve? and his unwillingness to leave the veteran home?

3. At the end, even if Mike had convinced Nick to not shoot himself, would they really have been able to just forfeit the game and leave? I don't see that going over too well.

4. Lastly, why does Nick send so much money to Steve in particular? and how does he even know where Steve is staying?