Again, the cops’ conversation shows that they were considering him to be in excited delirium, for which they are supposed to keep him restrained so he doesn’t flail around and hurt himself. And the knee hold was a CONSCIOUS hold. He did not pass out because of the knee hold It was purely to keep him from moving. His shortness of breath had nothing to do with the knee hold, because he was complaining of it (truly or falsely) before it was applied. He died of a heart attack brought on by his health condition and his drug use, perhaps exacerbated by the stress of being arrested and restrained. The exact same thing would have happened had he been restrained in some other fashion.
And he was not some good upstanding citizen entitled to a presumption of innocence and good faith even outside a courtroom. He was someone with form. An armed robber. So he had lost his chezkas kashrus.