Crucially, we're not talking about the consequences Dawkins suffered or did not suffer (a descriptive question); we're both talking about prescriptive questions: whether his posting that video should be considered wrong, and if so what consequences are appropriate and proportional.
Your one word response to Dawkins' pretty troubling juxtaposition of Muslims and rape, "Parody." indicates to me that you view parody as something that either means nothing wrong occurred or could occur (ie parody should be excluded from ethical analysis), or that things in the category of parody should be immune from any societal rebuke. You're welcome to correct me if I am misreading you on that.
My counterargument is propose a world in which people were able to make any racist or homophobic (or for example antisemitic) allegation and bake it into the premise of a parody. Should they be automatically immune from societal rebuke? If so, we open up floodgates; anyone who wishes to make racist or homophobic allegations will naturally just take the path of least resistance and sandwiched these in parodies and escape rebuke; it reduces more or less to society having no power to rebuke racist or homophobic remarks in general.
Conversely, if being incorporated into a parody does not exclude an author from moral responsibility for his remarks, then your justification of "[it's a] Parody" is clearly insufficient.
--
> What racist? There was no racism there
If we are talking about the video made by Sye Ten Bruggencate and published by Sargon of Akkad, then because it is a video we do not need to make any tortuous suppositions about the ethnicity of Muslims in the parody, you can watch the video and see for yourself. It fits quite squarely into a long history of racist caricatures of foreign figures or in cartoons, and even more so into a long and vicious history of presenting foreign or non-white men as a threat to white women.