I am sorry Smokey is so poorly. He is a very old boy. He must have gotten remarkable care to reach age 22. That is awesome!
The issue with his mouth is due to gingivitis or abscessed teeth.
It would be best if you could bring him to a vet. He will get an antibiotic and subq fluids which will keep him comfortable until his owners get home. Then they can decide if it is time to make a decision.
I would not call and worry them now because it could be dangerous for them to try and rush home in bad weather.
Please let me know how things go.
Bless you for taking such great care of him.
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