The VAR looked at the 'goal' and said "Check complete". And that was it. It would be better if it had been "Check complete, goal scored, no offside", regardless of what the onfield decision was. No room for ambiguity then.
Having heard the audio tape, the video operator (i.e. not any of the 'professionsl' referees) pointed out that the game not not restarted with a centre kick, and the goal was not showing on the scoreboard. The Video Operator was saying to delay the game, but the VAR ref said they can't - they've played on.
Why on earth wasn't play halted? They do if, say, the ref's microphone fails, so a delay would allow them to rethink the next step, such as the ref explaining to the managers, and continue with a kick-off.
The unusual, even unique, thing about this was that the VAR and ref knew an error had been made in real time. Often debates about was it offside etc are only cleared up after the match when the studio experts discuss it and the refs receive feedback, and make apologies if they had made a bad decision. In this case the decision was the right one; what happened next was absolutely shambolic.