Unfortunately the lesson is missing a report similar to the responses report of the quiz module.
As I am the original author of the quiz responses report many years ago I understand very well your frustration because I was feeling the same way when I was not able to view my student's responses to the quiz questions and I decided to create the report..
I think that would be a very desirable feature to have.
Please create a new issue in the tracker with "Issue type" set to "improvement" and component set to lesson.
Once that is done come back on the forum and give us the issue number so that all interested users of the lesson module can vote for it.