The problem, as I see it, is that the CBA sets up a process that asks doctors to make their best medical determination as to whether an injury is career-ending and yet uses a much lesser practical test to overcome an unfavorable medical opinion. The judgment of the doctors appointed to review Darius' case was that his knee injury was so severe that he wouldn't be able to continue his basketball career without severe medical repercussions. But the CBA says that if Darius can play in 10 NBA games for as little as one second each, then the doctor's opinion is thrown out the window. I suspect that if the league-appointed doctor had been asked if Darius would be able to make cameo appearances in 10 games in one season, rather than giving his honest opinion as to whether it is medically wise or even practicable for him to play anywhere close to a full NBA schedule, he would have said yes. By that standard, any former NBA player with a pulse could come out of retirement.
I know that it's not going to help the Blazers, but the current rule needs revisiting. As it is, a team can be harmed significantly for trying to do what management believes is in the player's best longterm health interests.