Actually cold makes my car even more aggressive.
I feel like we should go back to the basics.
Start with fuel flow, coils, and spark plugs.
Then all vacuum lines, BOV, turbo pipes (clamps, tears...).
Also, I would actually invest in a mechanical vacuum/boost gauge. It is much faster in response and shows ACTUAL values, not processed by ECU.
Something like that.
That may actually help a lot.
For the logs - boost requested vs provided, same for air/fuel ratio. We are missing something here and I bet it is a simple thing.
A long time ago I had a car that was missing under light throttle. It would idle OK, it would go fine WOT, but light steady throttle would miss and jerk.
Spent several days in the shop, took to another one where some great computer guys tested it. Nothing was wrong, yet everyone could feel the issue.
All checked out fine.
Until I finally took the book, went through all the setup, and sure enough - one stupid switch was intermittently working. It would miss ground from time to time and would cut off fuel.
It was a 1997 car with electronically controlled carburetor with cat converter. Not as complicated as 1.6T-GDI, but still.
The point is - had we gone through the very basics in the beginning, it would have been solved right away.
I was trying to think what the shop did.
Possible some grounds are missing or were disconnected and then put back on on the painted surface without cleaning off the paint?
The passenger side corner - there is not much of mechanical related to the turbo/fuel.
But are ground points.
Further down you have wastegate controls and vacuum lines.