I processed one of my old leghorn hens this past year that had a very large, multi-layered object in her egg canal that looked very similar to this object. It had too many layers to even count, it filled the whole palm of my hand and the center was dark and smelled very foul. The layers were soft and cheesy looking, foul smelling also.
I would venture to say she had been egg bound for quite some time and had adapted and lived with this inside her for some time. She was healthy looking, not thin or sickly, but she had stopped laying some time ago. This was a bird that was pretty old and only layed about 8 days out of 30 and her eggs were enormous!
I would say your hen was eggbound and may become so again in the future, so watch for symptoms.