1:30 As already alluded to by some of the commenters, the practical reason why they switched from (phonetic) Cantonese to English is because very few of the cast (if any) speak Chinese, and certainly not fluently. The Asian actors cast are from diverse ethnic backgrounds (Japanese, Vietnamese, Korean, Indonesian, etc.) and for most of them, English is their first (or best) language. It would be impractical to have them memorize phonetic "gibberish" for the whole stretch. But for story-telling purposes, the reason they wanted to go that way was for the sake of the characters. This is a show whose primary audience is the English-speaking Western viewer. And the characters were introduced to viewers speaking a foreign tongue for which viewers had to rely on subtitles. But this added layer tends to "otherize" them (to English-speaking ears), especially in a backdrop of other characters freely communicating in English. By having the characters communicating their Chinese to English, that layer is dropped and the viewer is no longer burdened with having to overcome that extra layer. It's the storytellers' way having us Western viewers accept the Chinese protagonists as "one of us."
9:00 Don't quote me on this, but from what I remembered from the movie The Shawshank Redemption when they hosed down and then threw that white powder on the Tim Robbins character before his incarceration, my guess is they're delousing the prisoner.
Also your question last week, because they're speaking English as Chinese, so the writers has added a few of their own slang words like onion is their slur against other Chinese and duck as a slur to describe white people
I heard some explanations, it's action show so its easier to speak English so viewers don't have to read subtitles. And also most of the Asian actors on the show don't speak Cantonese
