This vid was big news several years ago, and resurface with regular intervalls. not only on sites like this, but also occasionally in regular media.
Someone on another forum dug up a newspaper article interview with a police officer who recalled having heard of the incident and visited the victim (a well known mentally ill local homeless, who was a nuisance in the mall this dojo was housed), who although severely beaten, did not wish to press charges. At the time there was no video evidence, so the cop let it go.
The head of the dojo died a few years ago, after several years illness, leaving him unable to walk. The guy doing the actual beatdown was in jail for some unrelated serious crime (I do not remember what, but he was not going to be free again in a hurry) .