Marponi does not get better

Here is an update on the black male cat called Marponi, who is almost ten years old, and who had a mouth/jaw surgery; the fact is, as Danica told me, he does not get much better. The inside of his mouth is still inflamed, and Danica says it looks as if it has gotten little worse recently; you might remember that the vet said if he gets no better within a week of surgery, he should be put to sleep. However, Danica describes how he actually eats, drinks, goes to the litter box regularly, and really, really likes to be cuddled with... and he purrs...and purrs...So she does not feel comfortable with putting him to sleep.
When I notice that he is in pain, I guess I will have to do it, she says.
Here is the latest picture of Marponi. I think one can even guess by the photo that the poor old man is sick, but ...Danica claims she cannot start thinking about putting him to sleep when he still loves to be petted , and while he still purrs when he sees her. Other then that, he really does not like to go out of his little cage and play. He will at least have a peaceful end, after being thrown into street by his old family (Danica thinks he had a family because when she found him, he was neutered)