G.B.
My grandson was deaf and the foster mom realized it after only a few days. I told my daughter something was wrong but she didn't believe me. The ENT checked the baby, he was just about 6-8 months old and he didn't even respond to the bass drum right by his head. Loud high noises, nothing. The ENT told the foster mom that he wanted to do the tubes and it was okayed by the state to go forth. The ENT took him into surgery and when he started going in the inner ear with his tools to look around he found debris from past ear infections that the antibiotic had not cleared up. He had to stop everything and start cleaning out the debris. The surgery lasted almost twice as long as planned. The doc came out and told them the tubes went in fine but there was a problem with the inside stuff. He explained what he had done and that he thought that was 100% of the hearing issue. It was.
My grandson came out of surgery and could hear perfectly. He was so scared by any noise, he hadn't ever heard so much before. His ears had built this debris up over some time since he was so young. They got all of it and he still has NO problems with his hearing and is developing normally now at age 2 1/2.
So, let the ENT do whatever he wants and try it all. I hope it all works out for your child and since he hasn't been having deafness all his life I bet it's debris from a past infection that didn't clear up.