I'm replying just to let you know that at least one person looked into it.
I'm pretty sure this is not possible with XML alone. It is not easy with custom C# code, either. I just looked at the code, and it doesn't seem to provide any way to hook into a quest failure.
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Hello khzmusik,
Thank you for your very good and detailed answer.
Unfortunately, I had just as much feared it, but still hoped that I had overlooked something.
Unfortunately, that also means for me that I have to come up with a new concept for my "story mode", as that was currently mandatory.
In case you care.
The plan was:
The player is left to himself much later and he gets a fixed goal to survive.
At the beginning he gets detailed information about what happened and why he is there.
Then he receives consecutive milestones that he has to achieve (Craft forge, craft workbench, craft x cobblestone ...).
In the meantime, he is supplied with further information via airdrops, so that this also has more meaning for the game.
The player must have reached the milestones by day 70.
If he has done that, he gets a few points for perks as a reward and he can then build free and do what he wants.
If he has not managed to do that, waves of zombies keep coming until he dies and he receives a very strong debuff and no reward. I would even have liked to have him start all over again.
But I already have a thought how I can possibly get around it. Just take a look.
PS: sorry for the google translation