None of us knows how to true wheels - a fact that came to light when I read your earlier post. It’s on our to-do list. The bike is largely stock, but i did consider the dynohub. When I inventoried my battery powered stuff, I saw its virtue but I’m not sure if this tour, although long, isn’t a one-off, so I am trying to save money where the cost to me is inconvenience eg charging. The cost to get bike tour gear is surprising - it means it’ll be a long time until my wife lets me campaign to get the bike stuff I’ve been dreaming of for other bikes.... I should have started younger!
My previous suggestion to get spare spokes that match your wheels stands, but I think in an earlier thread I suggested a Fiber Fix emergency spoke for the group. Since it is likely that nobody else in the group would have spare spokes for their specific wheels, the Fiber Fix would still be a good insurance policy to carry in case someone breaks a spoke.
Breaking a spoke is very rare, but the best way to make sure it does not happen is to be prepared for it. If you are not prepared for it, the odds of it happening is much greater.
And it is possible to do that repair with the Fiber Fix on a drive side rear spoke without removing the cassette.