You should follow the doc’s advice, but ALSO take your baby to a pediatric ENT specialist. An ear, nose and throat doc who specializes in children’s conditions, can best advise you as to whether or not she needs an operation. If you are not satisfied with what is told to you, get another opinion, but go to someone who specializes in this field with children. They will have more experience and expertise than a regular ENT.
If this were my child or granddaughter, I persoanlly would not wait the 8-12 weeks with her suffering like that. I would want to get her checked ASAP, especially when the breathing is affected to the point that the baby is snoring. All potential surgery on a baby sounds scary to us, but if it becomes necessary (and it may not be), then you look for an excellent doc and do what has to be done. I would try calling ECHO for a recommendation for a doctor. Hatzlacha rabba, may she have a refuah shelaima without the need for further intervention.