Brief update: BMW Canada paid for 4 thousand and made me pay for labour in the amount of ~$CAD1600. Both turbos failed and had to be replaced. The car is not the same, it has half the power it used to. The steering is also severely damaged: it pulls from side to side depending on the slope of the road and is hard to control when the road is bumpy. The dealer noted that pieces of the car became fused and had to be ripped apart. I think the wastegate defect profoundly damages much of the engine. The thing is incredible turbo lag and this is no longer anything like the vehicle I agreed to buy.
I no longer want to wait to assemble a class proceeding, I will be suing on my own. Best of luck to everyone else. I will still consider posting my statement of claim as a template.
"How do you say "Toyota" in German? BMW."