Thanks. As I assumed the data between 330 and ~343 looks like full Rubbish, after that you can see an increasing barometric Pressure shortly after an increase of Gspd and Vsp. This would fit an Pitotrod thats been used in false direction. (Aerodynamic Drag induced by an Rollover e.g.)
Then the "Airframe" must have entered a more "stable" regime which has been hold until the Generators went out.(If data are correct)
Concluding: Nothing that helps finding the cause.