Teresa

Good advice from all the posters. For reassurance purposes, I lost my voice about the same time as your husband (I also had radiation and Erbitux). It was extremely frustrating as well as scary. It lasted about a month. At the same time my throat was so sore and tight that I could no longer eat any solid foods at all. No PEG so I had to drink Ensure Plus (VHC was only when I got desperate at the end due to its chalkiness and hassle ordering online as opposed to just picking up at grocery stores)
As for Alleviation , for me what worked wonders on soothing my throat and disolving the mucous was canned SELTZER water. I used it as a mouth rinse all throughout the day. The fizz cleaned out my mouth and cut thru the mucous. I did not drink much of each can, maybe a few swallows, the rest was swish and spit. Good Luck.