As far as I know, File Copy Modules do not act on the WIE. They describe files that the WIE should add to a computer when imaging it. If "Is Driver" is enabled, it will then use DISM to install the files on the newly imaged computer.
If you want the WIE to add drivers to a computer as part of imaging it, you configure that at Images -> {specific image} -> Image Profiles -> {specific profile} -> File Copy