You should start a bounty on the question.
Bounties are there to bring attention to the question, and you don't have to be the one who asked the question to start a bounty on it.
When you start the bounty, you have to specify why you start it, and there is a reason with your context: Current answers are outdated -- The current answer(s) are out-of-date and require revision given recent changes.
Once you've selected the reason why you start a bounty, you can also specify a custom message (3000 characters) to add more details about why you start it and what you're after (keep in mind that the new answers will still have to answer the question).
You will not be able to change the accepted answer, but you'll be able to give the bounty to the most helpful answer.