I would be more likely to believe the live round was in when she checked it as there is a bullet on the end of a casing for a real bullet, not on a dummy bullet, right? I think she would have seen the bullet if she loaded it. IDK though.
But aren't the dummy bullets bright orange, or neon, and pretty obviously a dummy? Am I right? IRDK? I would hope an Armorer loading a gun would recognize a dummy from a real bullet. Now, if she only opened the revolver and saw the rounds already IN the gun, I understand.