Well not sure what whoever is opening her up expects to find, unless they have a background in pathology.
I would say if it's a Brahma then likely it's the heat, those birds are extremely heavily feathered and the heat is a killer of all animals with heavy feathers/fur. And I know you are experiencing extreme heat your way.
Unless she was experiencing other symptoms such as runny nose/eyes, uncoordinated movement, not eating... etc.
Extremely sad at any rate. And a Brahma to boot - so lovely with that colouring