Choices, choices

I am interviewing for a fabulous local job being the Executive Director of the local Botanic Garden. It's a job that I'd like much better than what I've been doing, that would pay even more and be more satisfying. I really want to do Peace Corps. What if we can't work out the medical and I have to decide whether or not to take the job without knowing if Peace Corps is going to happen? I'm confident that we are healthy enough but it seems as if there are often issues. What to do?