The reason the sample size is so small is likely due to what I predicted in other threads. HI has a "no make stink" culture, meaning "live and let live." Unless the person submitting the petition or their family member was threatened, it's unlikely anyone would file that petition ESPECIALLY if the would-be-petitioner is a close friend or relative. Nobody wants to put someone already having a rough time through the hassles of having their guns confiscated for at least 2 weeks, having to attend mental health evals, defend themself in court, and then jump through the HPD hoops to try and have their guns returned. That process alone could be what pushes them over the edge.
People just don't trust the system, so relying on people outside the system to feed them red-flagged individuals is not going to catch the numbers they pretend it will. If over half the petitioned individuals were released and guns returned, it shows how one person's opinion of another's behavior is not a great indicator of the individual's tendency to commit violence. Even trained and experienced psychologists and psychiatrists can't make those predictions with any better accuracy, so why pin a petition to the subjective and untrained opinion of a person who just happens to make contact?