I am sorry to hear you are worried about Samson. I alway worry when a dog that is a great eater suddenly won't eat, and if he won't drink, I am even more worried.
My name is Rebecca. I am a veterinarian and will do my best to help.
Has he vomited at all? If you check his gums, are they a normal bright pink color, or do they seem pale? Can you take his temperature with a rectal thermometer?
This breed is prone to pancreatitis, and that could cause the diarrhea, and not eating. Or, he could have an infection, he could be sick from the chicken if it was really spoiled, he could have an intestinal blockage, there are many possibilities.
If he is not drinking, I am very worried about his being dehydrated. If he is dehydrated, that will make whatever is wrong with him even worse. Try this: Gently pinch skin over his shoulders, then let go. The skin should go back into position in less than 1 second; if it takes longer he is dehydrated. If he is dehydrated, and won't drink, he may need supplemental fluids given IV or by injection under his skin. If his gums look pale, he may be in need of medical attention.
If you can't get to a vet, try to get some kind of fluids into him: water, broth, Pedialyte. If he takes liquids, try to get him to take 5 to 10 mg of Pepcid (famotidine) for nausea.
There are places that may be able to help with vet bills. This website lists some:
Let me know how he is doing and what else I can answer or help with. Rebecca