You have to know first something about the design and the functionality of question/score slides, about the quiz scope:
Question Question Slides in Captivate - Captivate blog
This article offers you some explanation.
What did you change about that functionality? You tell about the feedback: are those the normal Success/failure captions (eventually shapes) or did you create custom feedback captions (or shapes) ? You can trigger an advanced action by the Success or the Last Attempt event, but as the name tells, the last one only occurs after the last attempt on question level. You don't tell about the attempts.
You can add shape buttons to a question slide: Buttons on Question/Score Slides in Captivate 6? - Captivate blog
To navigate a user to a content slide, is called 'Remediation', it is built in Captivate (since version 6) but has its drawbacks. More information: Remediation in Captivate
The problem with remediation is that the user will be returned to the question slide until he answers correctly.
It is totally unclear to me which events is triggering the advanced action that you mention, since you tell that you 'cannot' use the Success/Last Attempt event. All available events are in a table in this article:
Events and (advanced) Actions - Captivate blog
You will read that a question slides has only the On Enter event, and the two events mentioned already: Success/Last Attempt.
