You need to set the 'Work Item Reference' join between 'Work Item' and 'Wf Voting Event Audit' as an outer join so that the query will return results where a 'Wf Voting Event Audit' does not exist, i.e. no vote has been cast but the 'Work Item' has been generated. Read this section on table joins:
https://support.ptc.com/help/windchill/whc/whc_en/#page/Windchill_Help_Center%2FQBTablesAndJoinsAdd.html
And pay special attention to this point regarding outer joins:
Essentially, selecting a value for Outer Join Against means “allow null entries for the unselected table when joining against the selected table”. If a join is an outer join, the link arrow is green instead of blue.
So, in your case, you would want to have the 'Work Item' selected as the "outer join against" table when defiining the outer join.