As long as Martin is gone, Lamb should probably get it since he could prob score 15+ a game starting.
D-Mo has a chance in the 2012-2013 Rising Stars Challenge. Jeremy Lamb has a chance in the 2013-2014 Rising Stars Challenge. Royce White has a chance in the All-Star Game in the long trem.
Why will at least one of them be in the Rookie-Sophomore game? I don't think any of them will make it. The most likely is Lamb.
The only way Machado would be able to pull something like that off is for Lin to be out a few games. Unless he can pull off some amazing feats from the bench.