The bottom line here, folks, is that Joe Kovalchick owns the train set, and if he wants this caboose painted green to match the rest of the passenger equipment, so be it.
And just to set the record straight, this car was red for many more years than it's been green. Only in the last 10-15 years was it painted green and put into the passenger train. Note also that the steps have been modified to make it easier for passengers to board and alight. It also features overstuffed brocade cushions on the benches inside.
The Friends have done their usual fine job and have made Mr. Kovalchick happy. That's what matters!