According to his own statement he passed all the medical tests going into this fight with Cerrone, but is still claiming he is suffering from 'neuological problems' that all those medicals apparently missed. If you don't see why that is a huge red flag for the UFC then you have no sense at all. Who are they to believe, the medical professionals that cleared Diego to fight or Diego's lunatic life partner?You are right mate, its the main issue.
But we have a clue here to quickly answer to this one.
They tried to make him signed a discharge, that gives us a good idea of how the UFC lawyers perceive this situation. At least in diegos case.
They should have released Diego immediately when he started claiming medical issues that didn't appear in his tests. However, Dana likes him and there is a sense of loyalty there. Naturally the UFC is going to try to protect its business so they offered Diego to sign a waver about his bizarre claims. Diego wouldn't sign and the UFC isn't going to have someone fight for them that is claiming undiagnosed neurological problems.