I have that same ecu, but the tt’s with AJQ did not have the 052 turbo. Maybe newer models did, but from what I read its the AUQ that got the k03s and the AJQ the older k03
That's pulled from 1999 Audi TT which my dad bought as new. Definitely had k03-52 because the whole engine and ecu have been untouched until these last years, when the car passed to me. There is exactly that k03 "s" and the software is supporting it, it's k03s with that intake silencer thing and engine is AJQ. I know that every where it is written on the internet that it should be k03, but that has not been the case with this car.
I have also argued about this many times but I can't help but trust what I see.