Actually, the station fired the monster as soon as he revealed his true nature, had a police escort remove him from the premises, and instructed station employees to call 9-1-1 if the saw him on or around the property. No one could ask more.
The people who should be sued are his previous employers, who in all likely gave bland, uninformative references when the station contacted them as previous employers. Businesses are reluctant to reveal true reasons for an employee's termination, fearing litigation, but there is some precedent for holding an employer who fails to reveal information which might have prevented previous harm to a plaintiff.
In other words, you cannot do a Donald Trump, “you’re fired” without threat of being sued or worse, of being gunned down.
Under current law, woe be to anyone who gives a negative review, or reveals why someone no longer works somewhere. That's why they are bland.