Is my daughter's ear problem neurological?

Hi doctor,

My daughter has nerve hearing loss of around 50 % in left ear along with tinnitus since 10 years. She is 22 now. On the second of this month, she had put a drop of oil in the left ear. In finding herself uncomfortable, she visited an ear, nose, and throat (ENT), who put her on antibiotics for middle ear infection. Audiometry at that day was normal of the right ear. Next day, there was a slight discharge from the left ear. Two three days later, she had heaviness, which was fine after 2 to 3 days. During the time, she visited home, and on 12th, the heaviness of the head appeared again. So, we visited the ENT again, who extended the treatment for five more days. On 16th, she felt buzzing sound in the right ear also, and we visited another ENT. The doctor found a mild hearing loss in right ear, and immediately put her on Omnacortil 20 mg on the first day and 60 mg on the second. After that, 30 mg for three days and 20 mg for the next four days. On 17th, that is, the very next day of starting Omnacortil, audiometry was repeated, and this time, it was normal for the right ear. The doctors' observation was that probably yesterday she might not have responded properly or the medicine has covered the mild loss, but precautionary she continued with Omnacortil. The treatment is on, but she still has heaviness and slight pressure in the ear. We have consulted another ENT, who did an endoscopy and suggested that she has inflammation in the nose and Eustachian tube blockage. He started treatment for the same in addition to Omnacortil, which is on reducing dose. However, despite all, she is still feeling heaviness in the head and slight pressure in the ear. She had undergone complete blood test also, which came back normal, including thyroid, except she has a severe deficiency of vitamin D3 and B12. They were 7.93 and 173 respectively. In view of this, kindly suggest if this is a neurological problem. Should I consult a neurologist? She is depressed and scared. Thanks.