The scaphoid is the worst bone in the wrist to injure. The blood supply to the scaphoid is provided by a single vessel, and therefore is easily compromised. Long-term outcomes from scaphoid fracture are best when the wrist and thumb are completely immobilized until the fracture heals completely. Therefore, thumb-spica casting is the standard of care.
In other words, if KM were not a basketball player but some other college kid who broke his scaphoid playing ultimate frisbee on the quad, he would be placed in a thumb-spica cast that completely immobilizes the fracture site. He would be told not to play intramural basketball. He would be told not to play any sports at all for at least six weeks.
Long-term outcomes from improperly treated scaphoid fractures are not good. This is well known because many times subtle fractures of the scaphoid are missed by inexperienced physicians. It is distressingly easy to end up with avascular necrosis of the scaphoid, which can leave a person with a life-long problem.
They may well trot KM out for another game before this is all said and done, but it's the wrong thing to do.
"We are not provided with wisdom, we must discover it for ourselves, after a journey through the wilderness which no one else can take for us, an effort which no one can spare us, for our wisdom is the point of view from which we come at last to regard the world." --M. Proust