When creating a journal entry of type Calendar Event, there is an option to create it on behalf of another user. This does not always work.
An existing Calendar Event has an option when editing to reassign it to another user. This does not always work.
This issue was resolved in the 7.45 release of eTapestry, which was released on 11/04/18. If you continue to encounter this issue after that date, please chat with support.
Steps to Duplicate
From your user account, click Journal Add a new journal entry of type Calendar Event. Under the On Behalf of options choose another user. Save the entry and go to Journal. The entry will show on your Journal but not the other user's.