Clip 4 - 5 June 2018 Law 16
The Lions - called Red by the referee - drive a maul towards the Stormers' line. The maul falls down.
The referee calls: “Taken down by Red." Clearly, he believes that the Lions had collapsed their own maul and he lets play go on.
Law 16.8 DURING A MAUL
Players must not:
Intentionally collapse a maul or jump on top of it.
Players - not just defending player/players. That would include the Lions.
The reason for the law is to safeguard players against the perceived possibility of injury.
This is a common tendency in refereeing the maul.