I guess my answer would be like: "It's too bad they 50% killed me... but now, I'm not going to cry for my parallel dead bodies (they are a sunk cost) and I'll enjoy the money." So I would be both happy that I am in the winning branch, but also aware of the cost, so I would not be retrospectively happy about being forced to play.

Does this make sense? I would be both happy and unhappy about two different aspects of the situation. The part that makes me worry about the death of non-me's is that they were killed by something that was a threat for me too. (Something like when terrorists capture 16 prisoners and kill 15 of them and you are the one they release, and then somehow illogically they also pay you a lot of money. They did not kill you, and you even profited from the action, but that was not a personal decision on their side, just a random choice. So in some sense, they wanted to kill you too, and almost succeeded.)