" He was also concerned about me not being able to breath if it got bigger with Iodine?"
- Seen the pictures of the ones in the old days with goiters bigger than a handful??
They breathed and lived, no problem. The goiter grows outwards, not inwards.
As I see it, it is a doctor trying to force upon you something. If one hesitate, they use the scare-them method. They want to be in charge of your health. I cant chose for you, but the best I did was firing the docs.