I forgot to note that caveat, fair point. But it's implied he returned to work after lunch in his car, and that he was "confronted and criticized" for his reaction to the party, which seems like a light response to significant violence, so I'm leaning towards the less violent end of the spectrum there, on the order of something like a shove on the high end. Without clarification, that's just an assumption, but generally, the burden for proof lies with the employer.
Edit: Actually, the Link NKY article referenced in OP clears this up, and it appears that no evidence or testimony of any violence was ever offered. The first set of opinions are obviously one-sided, but it seems clear from the last paragraph in quotation here that there was no real violence.
> “They way [the Gravity Diagnostics employees] say it, they believed he was enraged and possibly about to get violent,” Bucher said.
> Berling has never demonstrated any violence, Bucher said, and someone who is suffering a panic attack becomes almost paralyzed with fear; they don’t often lash out.
> “Basically what the argument was is he was fired for having a panic attack,” Bucher said. “They made assumptions that he was dangerous based off of his disability and not off of any evidence that he was violent.”
> If he had made violent gestures, Bucher said, Gravity Diagnostics would have had grounds to fire him, but he didn’t do anything threatening.
> ...
> With ever-increasing incidents of workplace violence, Brazil said, the verdict sets a dangerous precedent for employers and employees that unless physical violence occurs, workplace violence is acceptable.