If you feel a question was incorrectly closed, then you should do precisely what you did: post here, on Meta. Since 5 people (or one mod/gold badge holder) considered it a dupe, the best way to change that is to make your case to the community and see if others agree with you.
You can also join the main [chat room-(http://chat.stackexchange.com/rooms/201/ask-ubuntu-general-room)chat room and discuss the question with other users.
If you have a similar problem and the dupe's solution doesn't asolve it for you, then post a new question. Make sure to link to the duplicate and explain that you tried the suggestions there, explain how they failed and ask for a different solution.
In this case, I can't really see why you don't consider it a dupe. Perhaps you could explain in more detail?