Not sure where you are getting your information on the whole 5 year thing.
Take a look at this sticky: http://community.armystudyguid...1056041/m/7107073106
They can look at all your NCOERs. Not just the last 5 years.
If you and the SSG(P) think that it is unjust, then go to the Brigade CO and fight it. If it is found that he committed an EO violation, put it on there and let it ride. It may only be a speed bump for him, it may be a career ender. Who really knows?