Where I live there are five hospitals that are linked together as one association where they share testing, billing, etc. Even though yesterday Caroline did say that she volunteered at St. Mary’s, it could be like our system here where she would have access to the records in all the hospitals in the association.
Then, as far as not being able to access patient records, it could be possible that a volunteer would be responsible for entering test results for patients as that would not be so far-fetched and something I could believe. If that were the case, she would have access to test results for Chloe and easily be able to get in there to change them.
All that said though, I could never in the world believe that she, the devout Catholic that she is, would even consider doing such a thing.