19 yr survivor and finally about to have comestic surgery.

I was diagnosed with rhabdomyosarcoma before my 3rd birthday and spent about 2 years in the hospital undergoing chemo and radiation to my head and neck area. The tumor was inside my nasal cavity bulging the soft pallet of my mouth and was centimeters away from my brain. Due to wear the tumor was located they blasted my jaw to my eye sockets with radiation causing me to have some long term side effects.I am now 23 and my lower jaw is underdeveloped causing my face to look more narrow than an average girl of my age. I have already had cheek bone implants and my next surgery is to have lower jaw bone implants put in, but the doctor who is to perform this surgery is telling me that the risks of getting an infection in my bone is much greater than getting cheek implants, especially with a person who has been radiated in that area, and he is scaring me because he is saying I could end up losing my whole lower jaw. He said the chances are 50/50 because he will be striping the blood supply on the outside of the bone and is relying on the blood flow inside my bone to hold up in the healing process, which is making me second guess my decision. I have been waiting for this surgery for years and you can only imagine how devastating it is to be told you could end up looking worse than you already do, I understand there is always risk in surgery. I had a somewhat minimal amount of radiation, 5080 CGY's to be exact and on Monday I will be having a CT of my skull so I have to take in consideration the amount I will be exposed to then as well. Can someone please give me information on this and/or successful recovery stats?