Having not seen the game.
If in open play, Green kicked and Blue caught the ball and a maul immediately formed - NO T/O (Blue Scrum)
If in open play, Green kicked and Green caught the ball and a maul immediately formed - T/O(Blue Scrum) [Law refers to an "opponent" (of the kicker).]
If in open play, Green kicked and It was unclear who / they caught it togethercaught the ball and a maul immediately formed, Blue Scrum [ Rational if with paly had caudgh it. Scenario 1 OR 2 would apply and in both cases it would be a Blue scrum so why not?]
If in open play, Green kicked and Blue caught the ball and no maul formed player straight to ground and a ruck formed instead.
We have an unplayable ruck rather than an unplayable maul therfore, ruck laws apply. so "The team last moving forward. If neither
team was moving forward, the attackingeam in their opponents half) team. Which means it could be a Blue or Green ball.
I am guessing that Barnes gave the scrum to Ireland. Is it possible it was a ruck and not a maul and Green were going forward?