>He has an accomplice who is watching the stream and texting info? Does the stream show the players' cards (never seen it)?

From the 4th sentence of the article:

>and the game was broadcast on a half-hour delay so that viewers couldn’t relay information from the broadcast to the players during the hands

It's entirely possible that as a former employee he has access to the system that is responsible for introducing the streaming delay and gets a real-time feed on his phone or some other wearable device.