I am sorry to hear this Lut, poor little Snoopy! I have no advice for the infection and feeding, but I think many more PT'ers had done it.

For the pill, Jasmine is terrible for it also, even if the pills are very small! I have found something that works like crazy: I use the soft cheese that you put in hamburgers or "croque-monsieur". Do you see what I mean? Sorry, I don't know the name of this cheese. I have tried with tuna and other food, but it is very difficult to hidde the pill enough. This cheese works very well because it is soft (you can also try the "vache qui rit" cheese, I am sure you know that in Belgium ), you can really hide the pill in it.
Jasmine is crazy with fish, but fish did not work at all in this case.

I think your Snoopy is just a delicate princess, like my Jasmine

Good luck, and kiss her for me, OK?