Mareks or eye issues??
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I see bubbles and swelling in the one eye, along with some swelling around the other, which could possibly be mycoplasma (MG) or another respiratory disease, but don't know what the little bumps are around both eyes. Have you seen any fowl pox in the chickens lately? This looks a little like it could be fowl pox, but I can't be sure. Fowl pox can cause infections in the eyes.
You should try to get some testing done or a necropsy by the state vet to find out what is going on. The bad odor sounds like coryza. Selling off birds from a flock where there is illness may spread it to someone else's birds. Turkeys get MG but not coryza, but they could probably be a carrier, I suppose.