If it ain’t documented it ain’t supported, that means if and when it breaks you can’t complain about it. I myself use this topic, but I have two other backup methods for when the topic fails, and it fails a fair bit.
Which means you could use it in production but when it breaks, you need to have a backup.
You probably shouldn’t use it in production, because, Twitch wouldn’t grant you a elevated rate for an “unofficial”/unsupported API. You need to check 11k users? Using an unsupported API on a thing with a limited connection/subscription count?
So the only “official”/supported way of checking live status is the Twitch API under https://api.twitch.tv/kraken
And the only supported pubsub topics are whispers and bits.
Of course I don’t work for Twitch, but sounds like you might wanna email dev success and outline your usage case, but this pubsub topic, is not in official use. Technically it doesn’t exist.