I cannot be sure just from the one photo, but the ones you mention as possibly oyster mushrooms may in fact be what we call Angel Wing (Pleurocybella porrigens). I find them here in the Great Smoky Mountains as well, I believe they are very common throughout the northern hemisphere. They can easily be mistaken for oysters. They are usually in groups like that, a bit small for oysters, and theres no stem whatsoever on them. They are not recommended for eating.
I am no expert, but that's my observation of that photo and my experience combined.
Good job not harvesting, there's always time for identification and research and returning another day.
Happy hunting!