I am not up on the law, but I do watch Animal Court with
Judge Whopper all the time. lol

If you get get medical records with a statment
from both your vet that the kennel cough did cause
the pnemionia and that the cherry eye "was defenitely"
the caused by the coughing or it is hereditary etc.
I think you would have a good chance
in small claims court too.
I would document your calls,
and any correspondance with the breeder and check
out to see if their is a lemon law in the state
you bought the pup in.
Maybe you will get some vet bills reimbursed.
Good luck and please keep us informed
on your puppy and what ever you decide.