You already stated the goal of protected question, so there's no real workaround on this protected question specifically.
That said, you need only 10 points (as, as explained in this blog post, so you can:
- Answer another question and gather 1 upvote
- Ask a question and gather 2 upvotes
- find 5 posts to edit for grammar or to improve formatting
And that will be enough to be able to add your answer to this protected question.