Your conjecture makes a lot of sense. That kind of professional risk taker, doesn’t just forget everything they know, once they leave that job, or become too old to case the bad guys. For many people, their first identity is that “I am a person who is loved and needed by (X) fill in the blank. For many, the fact that someone needs them, makes life worth livng. Such a relation of a Knockout victim will do whatever it takes to protect that source of affection, that who adds a priceless warm glow of acceptance into their lives.
The one big danger I see here is that with the resources available to them, a certain... Hmmm, Segment of an organization can profile and then target the right person to cause them to ‘snap’.
Then they let them go vigilante and once enough evidence has been gathered; create a two year sensational trial and use that to blow off the media’s attention from things that are much more serious to the country.