Early in the attempt to make Kyle open the safe, Ty racks the slide of his shotgun twice before ever taking a shot. The second time should have ejected a shell.
Nail guns have a safety feature that keeps them from firing without putting pressure on the tip, which means Kyle couldn't have fired it like a gun.
Suxamethonium IS a paralytic agent, but it has no anaesthetic or analgesic properties. The paralysis from 'sux' is so profound that respiratory muscles are paralysed - so anyone dosed is likely to die from asphyxiation. In addition, the half life of sux is pretty short - just a few minutes in normal subjects. So in summary, a character given the sux would be paralysed for a few minutes - completely aware of anything done to them, and possibly die from asphyxiation.
Rubber Knife. Bends against her throat when she is breathing, more than once.
After Jonah is nail-gunned through the boot to the burning money, he has a fairly lengthy exchange with Sarah, yet the fire at this point should have already engulfed him and made such casual conversation impossible.
When Jonah stops Avery from picking up the nail gun, he says it's not technically a nail gun until it's turned on. He should have said until it's plugged in.
While it's true that the diamonds are the hardest material on Earth, they can be smashed with a hammer or a pistol handle as they are brittle as all hard materials.