What's weird is that was the official story, but the recent story completely changed:
UFC Sakatoon Injury Update: Charles Oliveira Suffered a Tear in His Esophagus
In a Monday morning update, however, UFC officials revealed that Oliveira suffered a micro-tear in his esophagus.
A decade later, Charles Oliveira’s injury suffered against Max Holloway remains a mystery: ‘Nobody knows what actually happened’
A day after the bout, the UFC announced on its official site that Oliveira suffered an esophagus tear during the fight. Diego Lima, who wasn’t his head coach at the time but already a friend, was in Canada that week to accompany Felipe Arantes on the same card. He became Oliveira’s head coach some time later, and said what happened to “do Bronx” that night still remains a mystery.
“It was all very strange,” Lima told MMA Fighting. “Really crazy how it happened. So much so that even today nobody knows what actually happened. The hospital wouldn’t let him leave or return to Brazil because they couldn’t detect exactly what the problem was, he still had that paralysis. It was something very serious that no one ever figured out.”
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So this is maybe like how the UFC said that Pantoja dislocated his shoulder against Van when he clearly dislocated his elbow i.e. they just make-up whatever shit they feel like in the moment.
Because it's a decade later and Oliveira's coach is saying they don't know what happened, and yet the day after it happened the UFC claimed they knew exactly what happened.
I watched the fight live and multiple times since (only 90 seconds) and Oliviera gets hit in the face like twice (he eats a number of body shots mostly), he seems completely fine before he shoots for a takedown and kind of runs his head/neck/shoulder into the cage as he gets sprawled on. You can see him grimace as Max stands-up and pulls out of his guard, he throws some up-kicks, then as he stands-up he immediately grabs his neck and starts to turn away like he's injured and can't help but react like that.
I've never heard of a fighter getting an esophagus tear outside of this fight in boxing/kickboxing/MMA/etc. in 20+ years of following combat sports (including reading about fights that happened before I started paying attention). I don't know how you'd get a torn esophagus without getting hit in the throat/neck and already having a pre-existing tear; it seems pretty physically impossible on the basis that it's literally never happened in tens of thousands of recorded fights.
One of the weirdest fight results I've ever seen, still doesn't make sense.