Brodie Lee passed away at the age of 41 on the day after Christmas last year of a non-COVID lung issue. It was only known that it was bad enough that he needed a lung transplant.
Dave Meltzer reported in the Wrestling Observer Newsletter that part of the problem with Lee was that his lungs were damaged prior to his illness and death.
The belief is he had not been previously diagnosed with the issue prior to his lungs failing him. When doctors figured out the problem, it was tragically too late.
