They are generic part numbers... I think you're getting hung up over that and them not matching 100% identically. The ECU part number is inside the ECU itself and coded and not visible unless you have the ability to dump the contents of the ECU, find the address in memory where this part number and/or serial number is stored when the dealership writes your blank ECU using SDS II before putting the bike on the sales floor. For example, one such reference:
View attachment 1654734
I could go through and find other instances, the VIN number that was coded to an ECU I read out... etc. The part number on your ECU is inconsequential as it's generic and not how the ECU part number is stored in the code of the ECU or how we track/reference them in the software.
So when you (or your tuner) attempts to read the part number and serial number, it goes to the ECU, looks in these specific data areas and verifies that the data lines up. If so, your ECU is supported and the software offers to open the correct file for you. If not, it states this and your ECU needs to come to us to be read out and added.
Dollars to doughnuts you can send that to your tuner of choice, they'll be able to read the part number and serial number and be able to tune your ECU.