FWIW: I followed up with Lionel and my dealer and like Marty am optimistic. I don't want to use names of customer service people I spoke to as that could get into "he said, she said", suffice it to say that Lionel dealers should be receiving official instructions from Lionel any day now on instructions of what to do. I'll check again with my dealer next week.
I still encourage everyone who purchased the RPO cars and who would like resolution of the color mismatch to call Lionel and their dealer.
As an aside, there's an amusing history of us Polar Express train nuts, foamers, whatever you want to call us, who have long endeavored to lobby Lionel for O-scale variations of their popular traditional Polar Express line of trains. I remember the early days (2004-2008) very well; there were some spirited discussions back then, including a fair amount of criticisms. I get a good chuckle thinking of this history, but its all part of the fun and evolution of hi-rail