See that roadmap you mentioned, use that. There will be a definite feature list with each version number if the stakeholders want to drill down into it, just give the next version number and the current date its expected on.
Don't bother. If they've accepted non-man-made climate change liken the situation to being in a locked room that is on fire. Are you going to just sit there and burn because you specifically didn't light the fire? Or will you try to find a fire extinguisher.
How to work as part of a team - all the bootcamp candidates that've come to us only did solo projects.
How to read documentation - I know its not an easy skill to teach but so many of them will ask how to do something rather than investigate the docs themselves.
Pros and cons of different approaches, a lot of candidates seem to think there's only 1 way to accomplish something - usually because that's the way they were taught.
