That sounds like a lazy response from the dealer. That PCM flash was supposed to be for EXPORT RHO's specifically identified by VIN via the VIP inquiry process. Sounds like they didn't do that. Have you even tuned your ECU/PCM or watched somebody do it? If you don't do it right, you can brick your ECU/PCM (and in turn, your entire vehicle,) and thereby you have to be very cognizant of what you're doing.
Your dealer should be chastised by RAM for doing that in the first place, (it was for INTERNATIONAL RHO's bound for export!), and then to compound the situation, the response you received from Stellantis is more than just unacceptable, if I were Kuniskis, I wouldn't want people that incompetent working for me.