For the record, found this on reddit:
http://www.bbc.co.uk/news/uk-20645838
Apparently lots of other media outlets (Fox, per the link above and Huffingtonpost, in another story I saw) are not being very clear. The nurse that was found dead is not the nurse who revealed the info. From the article:
"Mrs Saldanha, a duty nurse who was married with two children, answered the telephone because it was 05:30 GMT and there was no receptionist on duty...
In the call, another nurse was tricked into revealing specific confidential information about the duchess's medical condition."