Zoom/Outlook Sync

Hello,  I need help before frustration overflows.

I have a user that their Outlook calendar is not syncing with Zoom 100%.  I have created a meeting in outlook and used the Zoom Plugin to help create the meeting.  The meeting is appearing on my Outlook calendar and on his.  It is appearing in my Zoom Client and Zoom Web Portal but NOT in his Zoom Client and Zoom Web Portal.  The opposite happens if he creates the meeting.  I really need the meeting and other meetings I create to show in his Zoom.

We are using MS365 and Outlook 2016/365 Client.

I have followed these steps: https://support.zoom.us/hc/en-us/articles/360000488243-Using-calendar-and-contacts-integration and given them read/write permission.