I don’t think I can give much specific advice, but it doesn’t seem like you’re putting much of a weight on what you want to do. For instance, it seems like you’re somewhat disappointed that 80k advised against working in AI ethics. If so, I’d suggest maybe applying anyway or considering good programs not in the top 10 (most school rankings seem to be fairly arbitrary in my experience anyway) with the knowledge that you might have to be a little more self-motivated to do “top 10” quality work.
Alternatively, it might be the case that you simply haven’t looked into Civil Service jobs as much in which case maybe spend some time imagining/learning about that path. You might find yourself becoming just as excited for that work as for the AI stuff.
In that case, it seems plausible that you (and your coworkers) will do more and better work if you’re not just ascetically grinding away for decades (and if they aren’t spending time around someone like that). Perhaps, a good next step is to shadow/intern with/talk to people currently doing these jobs to learn what they look like day to day?