Kyle,
I too had tonsil cancer and am now in my 4th week of radiation without a peg tube. I declined the offer and told them I will have 1 more surgery and that is to remove the port in my chest. So far I have only lost 5 pounds and am still eating. So go with your gut on this. If you feel you can do it without a peg try it. Worse case is they stop the rads for a couple of days and put one in. Good luck!!!