Do we know exactly what let go on this car? It's not the first RS3 posted that has burst into flames (that American video on the motorway comes to mind). Whatever popped and sent flammable mater presumably onto the turbo/manifold and ignited should be something to know about and pay extra attention too as a serious failure point on our cars.
I was recently looking at a flex fuel tune which would require an ethanol content sensor to be fitted. One thing that concerned me was plumbing the content sensor into the fuel line and the risk of bad connectors or installation. Having fuel sprayed out at high pressure could be catastrophic.
Given it was their development car you would hope that some aspect of their business insurance would cover it.