The wheel/joystick uses a similar chip as the proffieboard, and rather than using a standard driver guillemot has their own special DFU driver. That driver can’t tell the difference between a joystick and a proffieboard, and it comes with a utility that automatically re-installs the driver if you try to change it to something else…
The good news is that the guillemot dfu driver is only required when doing firmware updates to the wheel/joystick. In normal operations it is not required. This makes it possible to simply delete the GuiSTDFUDev dll from your system. Now windows can’t use it, the utility can’t re-install it, and while firmware updates to your wheel/joystick won’t work anymore, you will be able to program proffieboards.
This post has the details, please note that I cannot guarantee that this is a safe thing to do: