Hi Ton
I think if you were to place another module to a different page, you should use the Add existing module, but don't select the Copy. This allows the module to be "linked". If you create a copy, I don't think it will preserve the content because DNN doesn't tell the Wiki to copy all its content when copying this way.
Secondly, wouldn't it be easier to just create a DNN page and set the page to redirect the URL to your Wiki desired topic? Every topic has a unique URL so you can just link it.
Alternatively, just copy the content and recreate on another instance of the Wiki. It does double the work a bit though.
I hope this helps.