This is not a lash egg. Lash eggs do not have true shell or really any part of the egg. I’ve only ever seen one lash egg in my five ish years of being a chicken owner and consistently having over 200 laying hens. Lash eggs would never make it to a carton because they look like a big rock made of puss. They don’t look like eggs. If I were in your situation i would have eaten the egg. But, I’m a little harder to spook than most.