That was 9 years ago, I bet that's way too late to get any info about it.
The censor reason, if it's really true, is still complete bullshit, there's no problem with sex scenes after 8 PM. The show was shown way past 11 PM which is 18+ ratings wise, they even show uncut horror movies on those channels sometimes.
I think this was just a standard reply and maybe they didnt know what they were talking about. Going through the audio and clean up that laughter is something that just doesn't make sense. Even though the laughter sounds "dirty" it's still normal.
I find it even more unbelievable that someone emailed them to ask for this.