Please note my previous answer about degree programs generally. You are correct that a Masters in Criminal Justice is not the right choice. You already have extensive work experience in this area so you would be better served by obtaining a Masters in a new area of study that would add a different dimension to your profile. If you are technically inclined a degree in Computer Science or Information Systems Management or IT could fit the bill. Otherwise, a Masters of Business Administration should be considered. Executive MBAs from respected programs are a resume enhancer for the mature professional.
Once you pick the degree program seek out the college or university with the most rigorous and respected program you can find and access. Spend your time and money wisely as Masters degrees are not cheap. A well-chosen certificate program could have some value but you would not derive as much benefit as you would from a Masters degree.