No idea what Bren does or can do. Also, DNK is just a user of Tuneecu. If Tuneecu has a problem with the 2023 Euro 5 Rocket mapping, then so does DNK. I don’t understand the problem with 2023 Rocket mapping with Tuneecu. Is it that the available maps in Tuneecu are incompatible with the 2023 models or is there a bug in the Tuneecu app? One thing I find interesting is that Tuneecu is not able to read a map from the ECU with Bluetooth while Bren is.
P.S. I read the pdf file you posted. Not sure, but it seems as if the dealer overwrites your Bren tune, you may have to pay them $150 to modify your updated OEM tune. This seems like a problem. You should ask the dealer if he can refrain from automatically overwriting your tune when connecting to the dealer tool.