Thought the same when it happened, was screaming at the tv for an obstruction. No maul was formed and the ball carrier had two blockers bound to him and slightly in front of him . The “flying wedge” then bumped into ASY (Angus Scott-Young) on the way to the try line . The confusing issue was that the catcher in the lineout never completely let go of the ball , he and the #6 from the Lions both had hold of it when the ball was placed.
My first thoughts were obstruction and think a lot a refs would have ruled it that way, but the ball was never transferred to a player behind him.
Overall though a pretty high risk way to defend an attacking lineout .
It was a really odd strategy and even stranger decision on how the defend a potential maul that close to the line.
With the Laws clarification around mauls back in 2016 you will have noticed that the tactic of standing off the maul as a way of defending it now rare. The law was all about the how the ball was transferred and when.
Simply put if has to be brought down and then passed to the ripper to be passed back;
if there is to be a maul. If it's a maul the ball must be transferred to the back, and the maul can't move until it's been transferred to the last player at the back of the maul.
The Lions did the first two steps and as the Reds did not contest thus it was not a maul (need 2x from each team to be a maul). As the jumper still has the ball in his hands even though the ripper also has his hands on the ball, the ball is technically at the front as the first player (front) has it (jumper). Thus no obstruction (player with the ball can be tackled unimpeded).
The added risk in this situation are significant. If ASY (Angus Scott-Young) or any Reds player makes contact with the Lions "wedge" on the side a referee may see that as a side entry in to a maul or illegal tackle etc, and as the stand off was planned they could deem such actions as intentional and cynical.
The irony of this is laws were changed to provide the defending better opportunity to tackle the ball carrier and defend a maul.