Technically, a migraine straight after a head knock, then it’s still a concussion.The worst thing about this is that the narrative is now along the lines of, well even an independent umpire could have made the same mistake like it was some kind of innocuous event that if you had blinked you would have missed it. Let's ignore the fact that absolutely anyone else who witnessed the clash was horrified Allir came back on and that's not even to mention the whole "migraine bullshit" they tried to pull afterwards.
It's just ridiculous.