That sucks. I thought I was in the same boat. Almost two months ago I woke up and my Shepard couldn't walk, he could just lay there and cry. I took me a minute to realize what was going on cuz it was really early and I was half asleep. I just starting balling. We called vets, found one that would take him in. found it it was arthritis. He is only 5! But he's a big boy. We gave him meds and vitamins and he still limps and whines alot. I thought he would live to atleast 12, 13 years. Nope, not the big ones. Anyway, I am not a vet, but I love my dog too. I blow smoke on him now and he likes it. I've had cats that will walk up and literally take a big hit off the smoke, but not dogs. When I have my next harvest I will take some oil or butter and put in on some hamburger with white rice mixed in. I would start out slow, but he doesn't have a big ass tumor like your dog. It may not be good advice, but I would being trying something and anything. Good luck to you. I am also 6', but a lot fatter at 280 lol. I started crying and my girlfriend dove out of bed she said she never saw me cry in 13 years she knew something crazy was going down. lol. Now he is babied twice as much but it kills him to see the female running circles around him though.