Help needed - Results slide 'Review Quiz' button issue

I've built a 10 question assessment using a basic introduction slide, 10 freeform multiple choice slides and a results slide which calculates results based on questions 1-10. On the results slide I have a 'Retry Quiz' button (which works fine), and a 'Review Quiz' button. The issue I have is when I preview the assessment and click on the 'Review Quiz' button, it will take me through all of the questions and I can see the red or green bar at the bottom to show whether the question was answered right or wrong, however what it is not showing is the green ticks which should appear next to the correct answers. Basically, the learner can see which questions were wrong, but not what the correct answer should have been.

I'm attaching the full assessment, as well as screenshots of what the incorrectly answered question looks like when its reviewed (as you can see there should be 5 correct answers for that one, but none of them have green ticks), and also what the trigger for the 'Review Quiz' button looks like as well. As you can see, I do have the 'Show correct/incorrect responses when reviewing' box ticked.

The reason I have used freeform questions for this is due to the number of possible reposes which are required for each question (ie, the full list of the product features which our learners are being tested on). The graded multiple choice option only let's me put in 10 possible responses. I'm not sure if using freeform questions is what is causing the issue, or if it is something else which I have set up wrong.

Any help is much appreciated!