A reader writes:

The subtitles in question on the South Park video are an explanation of why the entire speech has been cut, not Kyle's speech itself. My Chinese is not good enough yet to provide you a translation, but I assure you that's what's going on.

Another writes:

The dialogue has been bleeped out because of threats from a Muslim group.
他们警告 SP 的制作人小心会有 Theo Van Gogh 的下场。
They have warned the producers of South Park that they ought to be careful, otherwise they will meet with the same fate as Theo Van Gogh.
Van Gogh was a Dutch director who made a movie critical of Islamic society
且于 2004年被枪杀。
and was gunned down in 2004.