Usually if you can get into an MD program there is not much to stop you also doing the MPH. Many programs infact make you apply to the MD program and then admit you to the MPH also if that is what you want. Some do have separate admissions procedures but the MD one is always the tougher nut to crack.
I've never heard of ncf, but that doesn't mean much - there are tons of good colleges I've never heard of. Narrative evaluations will be fine, AMCAS the central processing service for med school applications even allows for it on their application (ie it's been done plenty of times before).
I think the state epidemiologist (has MPH) here makes around $40,000/year, but pay varies depending on whether you are working in government positions (generally lower but better security) or private consulting companies, and obviously by seniority. I've seen epidemiology positions for $80k/year but I haven't seen many of those...however, there is more to MPH than epi. eg health policy, and I don't know much at all about that.
The camp sounds great. The only thing I would hesitate about is that come application time you get to list your extra-curricula activities and are specifically told not to list repeat experineces more than once. Thus doing the same activity year after year, while showing committment, is less 'EC padding' than doing something new every year. obviously there has to be a balance in this, but it's something to bare in mind.
health policy and management positions vary widely as well. you could work for a non profit for 35 K with only a mph. you could go into healthcare consulting, and push 80-100K. you could do md/mph, become a hospital administrator, never do a residency and pull down possibly >250K a year.
do searches for old public health threads. i'm a mph student, got any ?s just let me know