I'm sure this is being done in good faith, but HBS interviews are notoriously specific to the candidate. The adcom do interviews and they aren't blind interviews - meaning that they will go through your whole application (essays, short answers, resume, even LoRs) and come up with questions to really unearth the reasons behind certain decisions that you have made. Keyword there is "you". For a mock interview to be truly representative, the interviewer would similarly need to review the interviewee's application and then come up with really specific questions.
A mock HBS interview would be good to practice the interview setting, but I just want to caution that there is a lot more to be done by each candidate to practice for questions.
Good luck to everyone!