Hi Hecce
I understand all the live STREAMING - audio and video - is done privately, not through the WT.
Most 'first world' halls nowadays seem to have an audio stream set up - previously this was a landline telephone link-up, but now lots stream live over the internet using various 'private' apps especially designed for KH streaming - this way you get actual video of your OWN congeagtion.
Some KH's I believe use youtube to live stream to an invited audience - see below example.
Remember, those listening or watching the meeting live can be counted as meeting attendance (good incentive for elders to get it orking to improve attendance numbers!!)
This is in contrast to the video meeting RECORDINGS that are WT official.....
The BoE letter you should read is:
BoE October 22, 2015 - Re: Use of JW Stream
https://drive.google.com/file/d/0B5O25TquiW0xU0pmNVMzYkdtLTA/view
https://www.jehovahs-witness.com/topic/5133648026140672/now-you-dont-even-have-go-kingdom-hall-all-meetings-recorded-available-on-jw-org-if-you-have-password
These video files, recorded live at various 'real-life' KHs are WT official and are made available by the WT through their website stream.jw.org (these congregation meeting videos are NOT streamed live, but are available to view online 'on-demand' or as mp4 files to download)
The files are available for up to a week, before they are deleted and replaced by the next meeting.
Every month or so the congregation location is changed. There are individual video recordings for each language (yes, hundreds of them, including sign-language).
The videos are sometimes (unintentionally) funny as they really are just a bog-standard congregation and it is all effectively unrehearsed - it is a very real standard meeting, mistakes and all
Below is an example 'private' video stream, not from WT: