The accusations are that she tried to use her privileged position to get staff in her department - which is, let’s not forget, the one responsible for ensuring that everyone is treated equally in law - to arrange something specifically for her that would been she was not being treated equally. She didn’t ask them to find out is something was possible, she asked them to arrange special treatment.
When they refused - thus upholding due impartiality, as advised by the Cabinet Office’s ethics team - she allegedly asked one of her political aides to help. That person (who has no impartiality, or apparently ethical, remit, actually asked the course provider if his/her boss could be given special and preferential treatment because of her political position and was refused.
Whether these accusations are true or not, I don’t know (and nor do any of us). They surely, however, warrant investigation to prove or disprove their validity. I find it hard to believe that people would think otherwise.