Did i forget anything??
Yes, you forgot to do the most important thing.
You forgot to study the details in this topic on replacement before to do something and now you have what you have.
The 551L firmware has an CAN implementation incompatible with your original version.
Тhe IDs of the motor and transmissions that are broadcast on the CAN network are different.
ECU and TCM cannot agree among themselves, as they speak different "languages".
VCDS will not help resolve the issue.