If all the data required for personalization (in the message) is coming in from the event payload, then it is not needed.

No, that won't be feasible as "AJO Message Feedback Event Dataset" is a system dataset. You can potentially explore https://experienceleague.adobe.com/en/docs/journey-optimizer/using/orchestrate-journeys/journey-use-cases/technical-use-cases/custom-action-aep for collecting data in the custom schema...

Can you check the http status code by querying the following attributes from journey_step_events dataset for the respective journey ?  _experience.journeyOrchestration.stepEvents.actionExecutionError AS ACTION_ERROR, _experience.journeyOrchestration.stepEvents.actionExecutionErrorCode AS AC...

JOJourneyVersionsDs is an internal Dataset and not publicly available.

Is this happening for all the fragments or only this specific fragment ? If it is the latter, kindly try reconfiguring it and if it still shows the same error, kindly log a support ticket with client care team.

You can query the profile snapshot system dataset to find out the qualified profiles against your audience.SELECT count() FROM profile_snapshot_export_ID -- replace export id WHERE segmentMembership['ups']['segment ID'] IS NOT NULL AND segmentMembership['ups']['segment ID']['status'] IN ('realized')...

You can take a look at this related thread https://experienceleaguecommunities.adobe.com/t5/journey-optimizer-questions/offer-eligibility-vs-decision-eligibility/m-p/680086 

In the unitary event, advanced rule can be created to check if the current date is between the start and end date ranges. For the streaming segment, it has to follow one of the eligible query types mentioned in https://experienceleague.adobe.com/en/docs/experience-platform/segmentation/methods/strea...

You can take a look at this documentation https://experienceleague.adobe.com/en/docs/journey-optimizer/using/decisioning/offer-decisioning/get-started-decision/decision-management-guardrails 

This behavior is documented in the experience league page https://experienceleague.adobe.com/en/docs/journey-optimizer/using/whats-new/previous-rn-new/release-notes-2024 and is expected.