When it comes to residual risk, questionnaires can be a bit tricky. First, your inherent questionnaire should be completed by your vendor/product owner. But when considering residual risk, your subject matter experts should provide the data to determine if the likelihood, occurrence, severity, or impact of those inherent risks have been reduced. You may wish to include a risk summary with a rating to the subject matter experts and ask them to rate the risk levels after the controls have been considered. Keep in mind that there is a difference between stating controls exist vs. testing controls for effectiveness. Controls that exist but have not been tested should not reduce the inherent risk rating. I hope that helps but would love to hear from other members.