Essentially, he went and passed the impact exam of the UFC, and they pretty much confirmed that since he's exceptionally smart, his brain was making connections to overcome the already impacted areas allowing him to pass the regular impact tests easily, hiding the long-term effects that are sure to happen with the sheer amount of concussions he's had.
Apparently that shocked him into accepting his career was done.
Maroon's still a scumbag, but he surprisingly made the right call.
* * *
And we're now talking about POST-CONCUSSION SEIZURES for quite a long time according to him, he's been keeping them as hidden as possible.