Could it be "acceptable" to duplicate-answer, if the first answer worked, but was never accepted?

Question

The situation: you answer a question/OP mentions it works, but.../does not accept, does not upvote the answer, never comes back.

Then there is the exact same question, cannot be marked as a dupe, so you leave a comment, pointing to the unaccepted (but working) answer of the first question. However, OP has reputation 3, and cannot upvote, both questions stay seemingly "unanswered".

Is it acceptable to (re) answer the question on the second instance, so at least one of them gets accepted, and the oldest one can be marked as a dupe to the newest? (and no third version of the same question will possibly appear)?

These are the questions in my example:

first
second

Answer 1

If five people are willing vote to close question P as a duplicate of question Q because they are confident that the answer at question Q solves the problem in both questions, then probably at least one of them is also willing to upvote the answer on question Q.

I just read the questions, the comments on them, and the answer to question Q (i.e., your answer). Then I upvoted your answer and cast my duplicate-close vote on the unanswered question.