Security concerns and assurance on the Integration with Microsoft Office 365 Calendar

I need to know if the Oracle or Recruiter who is scheduling the interview with candidates will have access to the Interviewers calendar details. The IT Team is asking for assurance that this integration will not give users access to others calendar detail information. This will help us also to make a decision on "All User" vs "Single User" options. What does "Recruiters do NOT have direct access to the detailed calendar entries of interviewers." actually mean?