Vic Miller is one of the most competent athletic trainers out there. You have no idea what goes on behind the scenes and this sort of accusation is just uncalled for. Do you think when Halliburton came down on his wrist, Vic was just able to use his x-ray vision and tell if Tyrese had broken it? No, Tyrese told them he was okay, and figured it out that he was not.
I bet you anything that Grill had a slight fracture and was told there is no more damage that can be done and he was given the decision to play or not. What would there have been to lose for Grill sitting out the rest of the year? Absolutely nothing. If it was serious enough, he would've been shut down.
Concussions are one of the hardest injuries to diagnose. Players hit their head on the floor all the time and you don't know if you have a concussion or if you simply hit your head hard. I'm sure Bolton ended up having a minor concussion and if it was truly serious, Vic wouldn't have let him back in the game.