Why is the Questionnaire object not appearing? and why is there no data showing against the object?

A few things:

You need to add the object to the Obligation workflow [Workflow Configuration > ObligationWorkflow]

Then apply the permissions against the roles (your role) to be able to view this object. [User roles]

STEP 1:

STEP 2:

The questionnaire object will display the data that has come from a Survey in the Survey module after you have made the link via the links object.