Patty,
I am so sorry about your husband and that no one is willing to help him. I was diagnosed the monthe before he was, and am doing fine now. This think is so unpredictable.
I have a few thoughts. Gaining weight would really help him probably. Is he using a formula in his tube? If so, he might be able to get one that has more calories in it to help with the weight. Or if he's using a product like Ensure, there are some high-calorie versions of these too. See if he can meet with a dietitian (make sure s/he is a Registered Dietitian) about it. His ENT or cancer center can probably refer you to one.
Have any dentists suggested using hyperbaric oxygen treatments and then pullling teeth? This is a treatment that is used for all kinds of reasons, some very experiemental, but for dental work after radiation it is so proven that insurance companies will pay for it. See if you can find a cancer dentist (again, try at the cancer center for a referral) or mabye an oral surgeon with experience with head and neck cancer patients. I was advised to get all my teeth pulled before radiation and am glad I did.
And, while there is no cure for us, there is something better than a cure for this cancer. It's the HPV vaccine, and it will prevent HPV-related cancers, including cervical and many head and neck cancers. I am an advocate for this vaccine to be given to young teens everywhere; it has been proven to be successful for cervical cancer, and there are studies going on now about H&N cancer.
Best of luck to you and your husband.
Susan