I saw the CNN segment and for sure it seems on the face of it that the Chinese pilot could not understand the instruction.
I notice - flying in China regularly that the pilots never speak to the passengers. I assumed that the Chinese procedure was 'Pilots fly - cabin crew deal with passengers'. The cabin crew often make announcements perfectly clearly in (Mandarin) Chinese / English and sometimes in Cantonese as well.
One would think that if a cabin crew can be trained to understand & speak English then a pilot can be trained to speak & understand English.
But - I have worked in the past with a lot of non-native English speakers (in business) - they often complained that native English speakers used far too many slang terms or colloquialisms - or could even comunicate in a meetng with a slight visual gesture or a verbal inflection that would render the real meaning of a discussion or action point beyond the understanding of the non native English speakers.
If we are going to have more and more none native English speaking pilots - the lessons on communication have to be learnt by both sides.
There is no point at all raising your voice and getting frustrated if someone doesn't understand what you say - but you may have to refine how you chose to say it.