When creating a new Event, an unexpected page layout appears for the affected user.
There is no Record Type access to or none of the assigned Record Types are set to default on the EM_Event_Team_Member_vod object on the profile level.
When there is no default record type set on the profile level, the Page Layout Engine displays the page layouts randomly.
On the EM_Event_Team_Member_vod object, grant Record Type access to the Event_Team_Member_vod Record Type and set it as default on the profile level.
After making the changes, clear the Veeva Cache and refresh the Event metadata and Event Rules.
CRM Help Documentation: Defining Page Layouts