This + the guy clearly said that wasn't able to do the math for E30 but was confident with his E25.Agree with herox about canceling the appointment for now.
Not gonna lecture you, just state some facts. The 1.5T can only take so much. The first issue here is that you were running ethanol, a race intake, dp, fp, ic, tip and w7... without a custom tune. The KTuner tune is very good but isn't necessarily designed for FBO's. Then, even after going into limp mode, throwing codes and the shop telling you to take it easy, you still were gunning it?
Also, were you constantly monitoring your parameters like fuel trims and datalogging to keep tabs on how things were running leading up to this?
I run the community tuning reliability survey and this is a basic scenario that seems to cause many failures, unfortunately.
Good luck with everything. Hopefully your engine isn't too far gone. What codes did you actually throw originally (overboost?)?
Points out it was a pretty high concentration. Personally I wouldn't touch Ethanol without a sensor that constantly checks the mixture.