Ironmike,
I'm "4nana's" son, and I serve with you. I understand your question to be a 2-part question. 1) Yes, the Dress Blue is appropriate (w/ bowtie) for formal military & civilian events in lieu of a tux or Mess Dress. 2) If you are asking whether a cumberbund can be worn with the Dress Blue -- no, the jacket is worn buttoned-up, and your cumberbund would not be visible.
Please be sure & see your S-2 for a security brief since you're leaving the country (this is required). He/she may advise leaving the uniform at home for your safety.
Whatever the case, have fun & represent us well -- with or without the uniform.