Either post the entire setup, preferably with config sheets, or have a tech Altboot the device.
I know for a fact you have more info than the word "identical", there are a lot of details in setting up the printer to get to the outside world, then there is getting the smtp server right including port and encryption and authentication, add to that Firmware levels because things change (SHA-2 is the big one this year)
Your post has 0 relevant data to your setup, if you are 100% certain you did it right, tech can altboot and it will work when you set it up again.