Query where there is no related record

I have three tables, SpeakerEvent, ParishEvent and a junction table that joins SpeakerEvent to ParishEvent, JNC_Speaker_Event_Parish_Event

I need an Appian query that can tell me which SpeakerEvents have not been assigned to a Parish as well as another query that will tell me a Parish has not be assigned to a SpeakerEvent.

If I were creating a view in SQL, this would be done easily with a left join and checking to see if the ParishEventId is null.

SELECT SE.*
FROM `PMSO_SPEAKER_EVENT` AS SE
LEFT JOIN `PMSO_JNC_SPEAKER_EVENT_PARISH_EVENT` AS JSP ON SE.SPEAKER_EVENT_ID = JSP.SPEAKER_EVENT_ID
WHERE JSP.PARISH_EVENT_ID IS NULL

In Appian, I am trying to create an Expression Rule to do the same thing.  I tried several version of using a a!queryFilters as well as a!queryLogicalExpression.  I'm guessing that it has to do with the fact that there are no records on the other end of the relationship (JNC_Speaker_Event_Parish_Event).

if(
  a!isnotNullOrEmpty(ri!speakerId),
  a!queryRecordType(
    recordType: 'recordType!PMSO Speaker Event',
    fields: {
      'recordType!PMSO Speaker Event.fields.speakerId',
      'recordType!PMSO Speaker Event.fields.speakerEventId',
      'recordType!PMSO Speaker Event.relationships.event.fields.event',
      'recordType!PMSO Speaker Event.relationships.jncSpeakerEventParishEvent.fields.parishEventId'
    },
    pagingInfo: a!pagingInfo(startIndex: 1, batchSize: 1000),
    filters: a!queryLogicalExpression(
      operator: "AND_ALL",
      filters: {
        a!queryFilter(
          field: 'recordType!PMSO Speaker Event.fields.speakerId',
          operator: "=",
          value: ri!speakerId
        ),
        a!queryFilter(
          field: 'recordType!PMSO Speaker Event.relationships.jncSpeakerEventParishEvent.fields.parishEventId',
          operator: "is null"
        )
      }
    )
  ).data,
  null()
)

No errors are thrown, just no data and I know that there are records that satisfy this logic.

Any guidance here would be most appreciated.