Two pre cats pretty much tell us that it is a V6, but it would still help if we knew instead of leaving it for us to guess.
If it is a V6, there are still some issues to address. First, codes for bad cats is know to be thrown when there may not really be a problem. That s not the code you have though. For some of the V6's there is a TSB that tells about a new program for the PCM to widen the parameters for setting those codes. It may be worth asking your local dealership service advisor to run an OASIS to see if that TSB applies to your car. If it needs programming, it is not a free service so once you know if it will apply, ask how much it will cost to be performed.
It isn't likely that you are getting an EGR code from plugged cats. It is somewhat common to have EGR problems because of a plugged cat on the 4 cylinder engine though.
With that code, I would start by pulling the throttle body and cleaning the EGR passages behind it. If the problem persists, I would look at the DPFE next. Most lkely it is one of those two. If this clears up your problem, I would think about catching up with other maintenance next as needed, including cleaning the intake manifold, new plugs, cleaning the injectors (by adding a good injector cleaner to the fuel tank) and so on as needed.
If indeed it is a 4 cylinder I would get another opinion about the plugged cat. It is a bit more likely on the 4 cylinder engine.
If you fix it without replacing the cats, I would think about returning to the dealership and asking the service manager (not service advisor) to refund your money for a bad diagnosis. I think it is highly likely that you got a bad diagnosis.
