I agree - I have not been able to find anything about it after researching the issue on the internet. I taught kindergarten and pre-K for over 30 years and frequently had children in my classes that came from abusive situations. I had pictures of pandas and other animals with "black eyes" in lots of different units and teaching materials and never had a negative reaction from the children.
I hope you investigate this further with whomever said this and find what this is actually based on. And please let us know.