OutlookGoogleCalendarSync: Appointment update failed. Object reference not set to an instance of an object.

OGCS Version: v2.8.0.0 Installed or Portable: Installed Outlook: 2016

Outlook ← Google

0 Outlook calendar entries to be deleted.
0 Outlook calendar entries to be created.
4 calendar entries to be compared.
Comparing 4 existing Outlook calendar entries

Appointment update failed.
Object reference not set to an instance of an object.
0 entries updated.

Bug Description
I sync from Google To Outlook. (Outlook ← Google)

My Google account have access to another calendar but only in “See Busy/Free” mode. So all events in that calendar displayed with empty Title and empty Description.

When I sync that calendar (empty titles and descriptions) to Outlook for the First Time - everything is fine. However if in the parent calendar anything was updated in that event (time or title or description). Next sync will cause Null reference exception.

Steps to Reproduce the Issue

1. Create Home Google Account with Home Calendar in it
2. Create Work Google Account
3. Share Home Calendar with Work Google Account with “See Busy/Free only” permissions
4. Configure Synchronization to outlook from Work Google Account - selecting Home Calendar.
5. Create event in Home Google Account/Home calendar - put any description
6. Synchronize and make sure event is imported to outlook with Empty Title and Description - sync should complete successfully
7. Change anything in Home Google Account/Home Calendar (title or time or description)
8. Sync again, and you will see error:

Appointment update failed.
Object reference not set to an instance of an object.