What Riley needs to say is why these errors were made, eg what the VAR officials said to themselves and the referee b4 incorrect decision applied by onfield referee.
eg the Newcastle handball goal, is he saying the VAR officials , not just one person, with all the camera angles supplied didnt see the ball contact an offensive arm?He says it's an error, presumably to back up previous Laporte and Boly incidents that any offensive handball, in pigmol interpretation, leading to a goal is disallowed. So how could the VAR officials with all the camera angles supplied not have seen it. In pigmol interpretation it's nothing to do with clear and obvious, it's just handball or not by offensive player leading to a goal. It seems implausible that the VAR team can decide Laporte handled with all angles but not VAR team for Newcastle goal.
With Silva penalty, again he says it's an error. But what error? Did the VAR team decide they wouldnt have awarded a clear penalty. Did they decide not to use pitchside monitor, was that the error? if so has riley decided because hes had to admit errors that VAR will now instruct onfield refs to review this type of incident or have they already sold the pitchside monitors to Champions League Officials.