The commentators can hear VAR dialogue or are at least informed of what is being said by a producer. This isn't really new, they reference it often.
I don't think this is the case. I believe they get a message/signal (possibly even something colour coded as I've heard some say, "it's gone white") to say something is being reviewed and then that it is cleared OR decision given, e.g., goal stands or ruled out.
This would explain how the TV commentary can sometimes reference something like like, "it's going to stand" or "United/Liverpool/Chelsea will be delighted with this news" before or at the same time as the referee signals the outcome.
The audio is only every released in very exceptional circumstances and then only if there has been a lot of noise from one or more of the 'big' clubs. I could be wrong.
