I haven't read the whole history but did all her symptoms happen at the same time? It's just that it's possible for a bun to have more than one thing wrong at once so it could be worth treating for EC and inner ear infection just in case. I'd check the ears visually too if she's a little unbalanced they can have trouble cleaning there own ears which can make them itchy, increase the risk of infection.
If she's elderly/has mobility issues it might be worth discussing pain relief with the vet as that can help with arthritis etc. too anyway.