Rob

You can start by asking how many neck dissections each surgeon has done in the last few years and if any of them had "complicated" ones like yours and how it came out. Of course, you might not get any useful responses but generalities. I often wished that hospitals would keep statistics on their doctors that they provide to patients: Dr X has done 100 NDs, Dr Y has done 10 NDs etc.
One other source may be local magazines: the Washingtonian runs a "top doctor" issue every year where it surveys doctors to ask them which ENT, Cardiologist, Gastro, etc the doctors themselves would go to. They publish a short bio on each winner. That made my choice easier as my ENT surgeon had been a winner for cancer surgery each year plus her husband had oral cancer so she empathizes with her patients' travails and is very sensitive to minimizing side effects of surgery. She backed my initial decision to refuse the ND the first time around,