- The blurb is basically good advice but the wording could be improved.
- This isn't what bounties are for.
- Don't be overly concerned about the dupe, yet. Think of it more in terms of "when" than "if".
The point of the bounty system:
Bounties are good for the author of the question when no good answers have been received.
Bounties are good when you find a question that has not received a good answer and it is already worded well to accurately describe what you, also, would like answered.
Usefulness of bounties
If an older question has been referenced as having the answer, it means it already has one or more answers that have been indicated as good, either by upvotes or being accepted. So that question, as asked, is already well answered. What would a bounty accomplish? Even if it produces more answers, they are likely to be similarly not helpful to you ("insanity is doing the same thing over and over and expecting a different outcome").
Applicability of bounties
Bounties are a tool that is available for people to use voluntarily to attract answers. It is not intended for shaking down questioners (Sorry, that's already been asked. If you don't like the answers and want to try to get more, pay a bounty).
When good answers aren't helpful
If the answers to the older question are decent but don't answer your question, it means there is something about your question that is different from the older question. Asking a new question doesn't mean re-asking a question that will also appear to be a duplicate. It means asking the question in a way that clearly differentiates it from the older one. The blurb should probably be revised to include a suggestion to re-ask the question in a way that clarifies the difference.
When the older question has poor answers (even if upvoted or accepted)
I've seen a lot of proposed duplicates with a promisingly similar title, even a well asked question, and answers that meet the minimum requirements that allow it to be used for this purpose. However, the answers aren't really useful and it isn't clear why they were upvoted or accepted. These shouldn't be proposed as possible duplicates. When they are, and the uselessness is identified, they should be withdrawn. The first priority is getting questions answered. That shouldn't take a back seat to housekeeping the duplicates.
When the older question is identical but lacks a useful solution
The example you cite is one of these. The OP verifies that the question is the same, but it doesn't offer a solution. Why would a duplicate question attract answers the original wouldn't? The answer to that is it doesn't matter. Consider three time frames:
The older question is more than, say, a year old, especially if there have been changes in the interim, like new software versions. There is a benefit to getting information updated. Asking the question anew will pull current information from fresh eyes. The result could be a conclusion that the older answers are still good.
After the newer question has had time to run it's course (say a week), it can be re-evaluated. That's when knowledgeable decisions can be made on whether the question should remain on its own, be closed as a duplicate or merged, or even become the new standard due to better answers.
The older question is more than several weeks old. In this case, its active response period is passed. The question isn't going to attract more answers without some kind of action. If the older question can be improved and bumped, that's preferable to another identical question. But if there really isn't something to improve, and the question hasn't been fully answered, the new questioner deserves their moment in the sun.
The question should be allowed to run its course, after which, action can be re-evaluated. If it has attracted no upvoted or accepted answers, the system will delete it after it's closed. If it does attract answers, they're answers we wouldn't have otherwise had.
The older question is also new. This is a special case of a special case, and I'd probably make an exception for this, especially if the older question is less than about three days old. If the older question is identical and still in the active response period, I would point this out to the new poster and suggest that they delete their question, at least temporarily. If no useful solution appears, they can undelete their question and edit it to clarify things relative to the older question.
However, if they wanted to keep their question open, I would let them. A new user has certain benefits on their own thread, like the ability to ask for clarifications in comments, which they lack on someone else's question. After the question has run its course, we can do housekeeping on duplicates.
Duplicates are redundant clutter
Yes, they are. People looking for answers have a few extra posts to look at. But when they're trying to find a solution to their problem, they don't complain about redundant information. Dealing with duplicates shouldn't create obstacles to people asking questions and getting answers.