by Tim Hunt.
Can I ask you to take a step back here. 'Managing quiz passwords' is not a goal. It is a means to some end. To what end are you adding passwords? How does this help your teaching, your students?
Once whe know what you are really trying to achive, we can then change your question to be: What is the most effective way to do X? rather than What is the most effective way to manage quiz passwords?
That is likely to lead to a better final solution.