Insurance companies never pay out for "suicide by cop". If you put yourself in guaranteed death situation, then the policy is void.
When Sam is keeping his sniper rifle on the subject at the end of the episode Who's George, the bolt handle of his rifle is up. This means that the breach is not closed and he would not be able to fire. When the camera cuts to him soon after taking the shot, the bolt handle is still up.
When Sam is taking the shot at George, the bolt on his Remington 700 isn't in the proper position. The bolt is up, not down and locked. The rifle will not fire that way.
In the scene with the snipers on the roof, just after the shot is taken you can clearly see the bolt on the rifle is in the uncocked position indicating it was never cocked to fire.