Let's see how long this video stays up. Lots of sordid things going on here -- the offending footage, shot by an ostensible video journalist, was edited out, which isn't my understanding of what journalists are supposed to do. This appears to be something of a pirated version.
The video largely speaks for itself. Lightweight Brandon Rios definitely is mocking the Parkinson's disease of Manny Pacquiao's trainer Freddie Roach. Whether Antonio Margarito was mocking it too -- or just saying Roach was scared -- requires some understanding of Spanish, and maybe a generous spirit even then.
(h/t BLH and @milogeorge on Twitter)
[UPDATE: The unedited video has, naturally, been pulled from YouTube, but Deadspin is hosting it here. And you'd be happy to learn that the original impression of Roach was all a big mistake. You see, they didn't know he had Parkinson's, even though it's one of the two main things anyone knows about Roach, the other being that he trains Pacquiao.]