"Unless there was a recording, it's all "he said, she said""
I used to work in the governance team for an OOH GP service. The initial contact with a GP is via the phone. We'd sometimes get complaints in from patients and we'd then ask the GP for their version of events. It could be very difficult to marry the two versions. Then when you pieced them together with the call recording you realised that the patient's version of the conversation was a sort of distorted mirror version of the actual conversation. The GP's version was also distorted, just in a rather different way.
Anyway, it's deeply unreasonable to want someone sacked because of a story in the DM. Just let her employer go through due procedure. Makes a dull headline but is actually fair to the employee.