Tammy, I have to agree with much has been posted here, not necessarily directly. The theme I see is that each case is unique, and your Doctors are examining the situation your husband presents in totality. I think the old surgical approach of "when in doubt, cut it out" has been replaced, thankfully with a more reasoned approach. I had a neck dissection during my surgery, and while I am glad that it was done, there are the longer term effects that also have to be given consideration.
I had 56 nodes removed, none returned positive. Now, 5 years out and living with the reality of a great deal of fibrosis throughout my neck and upper chest that severely limits my range of motion, there are days when I really wonder about the decision to proceed with the ND given there were no signs of metastic disease prior to surgery.
Those ponderings do only last for a moment, but they occur. I think that if your Doctors felt there was a legitimate need to consider an ND, they would do so. Of course, having another ENT evaluate the case is never a bad thing either. Good luck on the ongoing treatment plan