The multiple insert server behavior is supposed to create a hidden field based on the name of one of your repeated fields. However the hidden field on your page was named starting with "LockOutChecked" even though that wasn't a repeated form field on the page. My guess is that you renamed fields or removed them at some point (maybe moved from a checkbox to radio buttons) and didn't rename the hidden field properly.
I renamed it to start with the name of the other repeated field on your page: "QuestionID", and that appears to have solved the problem.