So I was reading through some places in here and I found an answer to your question:
The rule is you can't be paid for the same disability twice. If the military gave you severance for it; you can't get paid for the same condition by the VA until the severance is paid back. Most people get separated for the 10 or 20% rating but when they get their overall VA rating its usually much higher so they get money. They only take back for the same conditions they paid severance for that the VA awards a rating for. All other ratings, conditions, whatever are not touched and they are paid to the veteran since they were not awarded severance by the military for those other conditions.
I didn't know how it worked since some lost everything, some lost half. I think this would help you have an idea.