Actually, they are not. They only advise participants to get tested if they show symptoms. So it's possible that a bunch of people on the vaccine are getting asymptomatic cases.
That’s not good though... really could but a kink in establishing herd immunity until everyone is actually vaccinated.
b) It's likely that it is protecting against those. But hard to specifically prove that it's protecting against each and every symptom. I think the hope is that if you don't develop lung issues, you are unlikely to develop long term damage.
Maybe I'm misunderstanding the data here. It seems like we've only directly proven that the vaccine has been effective at reducing the normal symptoms (coughs, fevers) to the point where candidates don't seem to be prompted enough to go get tested anymore. It doesn't directly prove those candidates didn't get covid.