I appreciate that, MLB12 - I called a couple of the Mopar vendors and two dealerships' service departments. Standard response is basically "if it doesn't say the part is for a 2021 then it probably won't work" but have no basis for actually knowing that it won't work. One service rep said they have never installed one in any model year truck and did not know if the harness was still there in the '21s. He also said that the system would have to be "reflashed" to the tune of $150 for the player to be recognized. I really would like to add the Mopar CD player and can do the install myself but hesitant to buy a $100 part that can't be returned because it is considered electrical...might just have to remove the center console (which is not too difficult thanks to YouTube) and see if that harness is present and go from there...
Here's a bit more information for you to digest.
The part number for the CD player that is in the '19s(DT series not DS) is 68335565AB, that supersedes 68335565AA, and they're available in numerous places from $90.00-140.00 USD, so price and availability is there. I haven't had a chance to compare the two(2) openings between the '19, 20, and the '21 to see if they are in fact the same dimensions and shape. I suspect so, but I'm not assuming that either. I can't see them being different, but who knows?
The next item is the wiring. It's very possible there isn't a pre-existing harness to plug into the CD player. In looking at the 52 pin connector for the '19 vs the '20 and '21, pin(circuits) cavities 7, 8, & 9, aren't even populated, so that would have to be changed by adding those pins in, so not a real big deal.
Where the unknown is concerned is the dealer is correct about reflashing the truck, but I must say $150.00 strikes me as a bit of highway robbery. Around here more often than not it's $50.00-75.00, sometimes even no charge. But I digress.
Flashing IS NOT a simple given. In the background the VIN has to identify whether or not a particular option can be flashed in, say when installing the factory trailer brake controller, or adding in driving lights, etc. If the option isn't there all the attempts at flashing in the world won't make it happen. I currently have my dealer service manager checking to see if it is doable. I may not know for a few day, but once I find out I'll let you know.