Sorry about you hearing loss.
Ear Nose and Throat Specialists can specialize further in specific areas (I have an ENT who is neurotologist). So, you may learn more by finding someone with specialized knowledge of your condition.
A close friend also lost hearing in one ear due to a virus. She has specialized hearing aids now.

I do know a couple of people who have had this happen after flying. Both of them now have cochlear implants as that hearing did not return.

When I fly, I always take antihistimine before boarding and chew gum during the flight. I often had a 'full ear sensation' along with popping when flying. My ENT told me to do that.

I have had progressive sensorineural hearing loss for decades so this was done as a precaution.

I've fortunately never had this happen to me after a flight, but I have heard that it does occasionally happen, though it's not widely known by the public. It has something to do with the change in air pressure and its effect on the fluid in the inner ear. This may be why some who are vulnerable to ear damage may be advised to use antihistamines while flying, because they tend to dry up the fluids in the head.

I'm surprised the doctor hadn't known about this, and the virus story seems a really ridiculous cover for their ignorance. Please, find another practitioner. Look for help at a medical facility doing medical research, in your area, perhaps at a university, where there will be more specialists. Or a place like the Mayo Clinic.

I hope you are successful in finding relief. So very sorry this is happening to you.

Barbie I am so sorry this happened to you. I am going thru something similar so know how scary and frustrating it is. On Feb 8 I was sitting in my car in the parking lot of my dentist office when I suddenly went deaf in my left ear. I asked the dentist if it could be related to my teeth cleaning and was told no. I went home and hoped it would pass. Few days later I went to an Urgent Care as my Primary Dr didn't have any openings for a few weeks. Dr @ Urgent Care said likely allergy related tho I've never really had allergies like that. Put me on a 1-week low dose taper pack of Prednisone. And told me to use Flonase allergy spray. No change. I'll try to shorten this. Finally got into ENT at 3 week mark. (2 wks is really the max for starting effect treatment in most cases) and started high dose prednisone followed by 2 wks of steroid injections thru eardrum. No improvement. Had excellent hearing in both ears prior. Now deaf in left ear. No speech discernment at all. Dr said it was likely from the C Vax or the sonic tool at dentist office as both have shown rare cases of SSHL. He just told me to come back in 6 mths for recheck. Felt very dismissive. Have now gone to highly rated Audiology group who did much more extensive testing. Am looking into a bone anchored hearing device - Osia. Hearing loss is a always difficult but when it goes from 60 to 0 in seconds it's very traumatic and scary. I found it very difficult to find help & fast enough. No one acted like it was a medical emergency. I've learned so much now but not in time for me it appears.
Barbara