Welcome. I had alot of worries also. I started with 65% hearing and I was terrified of losing it. Well I lost it, and it has not been any big issue at all. Really a minor inconvenience at most. Mine was 3.5cm at surgery time, and I had an excellent result, no facial issues at all. So don't worry too much about 3cm being too big.
Main thing is to pick a very experienced team, which gives you a really good chance of a good result. I do not know the doctors you mentioned, but I am not in TX. This site does have a list of doctors for each area. Let me know if you cannot find it, and i will try to help locate it.
I was the king of stressing while I was deciding. But I made it through, and you will too. Get with experienced doctors, and you will have a great chance.