It's possible, but can you cite another example of when a news article caused a recall to be issued a couple days later? It seems unlikely - usually takes months if anything happens at all.
Yes I think that. This was on local news early in the morning, just to cite one source from which I rarely get hacking stories. Normally they just talk about weather and how the elderly are getting scammed. This test occurring on a public road created an effective visual, that pushed the story into many more media channels.
I think 'hackers turned off the breaks on a car with a reporter in it at 70mph' would have made headlines even if it took place on a test track. It's a juicy story with plenty of 'it could happen to you' scare factor built in.