According to the documentation, a file is a duplicate if the original name is the same and the capture date is the same and the file size is the same.
So renaming doesn't affect duplicate status.
If you really want to import a second version of the photo (which I generally think is a very poor idea, maybe you could use a virtual copy, which is a much better idea), you could uncheck the box that prevents duplicates from being imported.
Since LR thinks some of the pictures are already imported, go to the Library module, find one of the "previously imported" photos in the grid, right-click on it, select "go to folder in Library" to see where LR thinks the file already exists on your hard drive.
I was using scripts and photo merge to combine multiple images so I would not think it would recognize the "original" anymore. For example I combined IMG_1230 toIMG_1235 and named it Goldnuggetbear. How would LR recognize it even as a duplicate? It's very frustrating because it is not letting me control what I bring in. It is hours of work I don't wish to duplicate. Help