I don't know anything about it, sorry, but I did find this on wikipedia-
Laryngomalacia becomes symptomatic after the first few weeks of life, and may get louder over the first year, as the child moves air more vigorously. It generally resolves spontaneously by the second year of life. In rare cases (less than 5%), surgery is necessary. Most commonly, this involves cutting the aryepiglottic folds to let the supraglottic airway spring open. Treatment of gastroesophageal reflux disease can also help in the treatment of laryngomalacia, since gastric contents can cause the back part of the larynx to swell and collapse even further into the airway. In severe cases, a temporary tracheotomy may be necessary.
I might get another opinion, if I were you. I mean 5% only need surgery- is the doctor sure that your child really needs it, or will it resolve itself?
HTH, A.