That is a shame and I am genuinely sorry it died. It can be very upsetting loosing a frog so soon after acquiring it. Look at the situation as a learning experience though. You did the right thing by not introducing it into terrarium with another frog that is otherwise healthy. Search the forums and do some research on cohabitating different species, quarantine procedures and general health and disease. There is a lot of information out there today that wasn’t there 30 years ago when I started. Also beware of “breeders” of certain species. Many of them are just dealers who call themselves breeders. There are a few legitimate people who do breed this species but there are many more who sell cheep wild caught specimens and pass them off as CB. It is cheeper for them to import large numbers of a common species rather than put in the effort to breed them. I still suspect you got a WC individual that may have been stressed and unhealthy from the get go. Nonetheless I am sorry for you. Good luck though and don’t get discouraged.