Hi there!
I don't think Duke is out of reach, but it is a competitive program, so I think having a backup or two is a good idea. You seem to have strong work experience, leadership, and community involvement. I think 10 years is a great fit for most EMBA programs, in fact I suspect many full-time programs would think you're too experienced. So with the GMAT...it's a bit less important for EMBA programs because they tend to value things like your work experience, leadership potential, professional references, etc. much more than test scores and GPAs (which are not very recent). So I don't think you need to retake but your lower Quant score could be a concern. Did you get good grades in quant courses in undergrad, like Stats or Calculus? Are there other ways you can demonstrate your quant skills via your recent work experience? If so, then it may be less of a concern. By the way, the IR section is not very heavily weighted and some schools don't really factor it in at all so I don't think that will make a significant difference, but it is a nice data point to have!
As for other programs...if you're drawn to the international nature of Duke's program, then I would check out UCLA Anderson and Georgetown, which both have global EMBAs. Another good option for you to consider might be UNC Kenan Flagler.
Keep us posted if we can help with any more questions!