Bomb Threat Karen aside, isn’t it against security regulations to knowingly separate a passenger and their bags?
Here in Canada, if they’ve already loaded your bags on board, they usually wait until they’re sure you’re not boarding. Even calling your name on the PA (repeatedly) … because it’s better to delay the aircraft by 5 minutes for you to board than it is to delay by 15-20 minutes as they try to find your bag and remove it.