Get a 12v relay and tap it off the reverse light feed in parallel to trigger the relay (grounding the other side of the coil) if this doesn't cause an error you can use the reverse light feed to trigger the relay while also feeding the reverse light and use a separate feed to the relay to power the pdc.
If the relay gives a bulb fault then the only way I know of is to code out the fault so the ECU no longer monitors the reverse bulb(s).

You'll need to be sure that the reverse light circuit is enough to power the relay as well as the reverse lamp it should be but I have to say it.