That is because the victims are Chinese. If the victims are black, I am sure they will go to jail. From the leaders such as Trudeau to the villans like this couple , hating Chinese become their current sports.
I think they're counting on Asians not being litigious. Also it doesn't appear this couple has a lot of money if they request assistance of counsel from the government.
I strongly suggest that the assaulted worker find a good civil litigation lawyer and sue the pants off these scumbags. With the unequivocal CCTV evidence it'll be a sure win.