While bar raisers can't make hiring managers take a candidate they don't want, they can absolutely "veto to hire" for Amazon.
It just means that Recruiting needs to find another team, which the candidate is not guaranteed to be interested in. And that team's manager will also want to interview the candidate, so an offer is not guaranteed again.
In other words, you can recommend recruiter to see if any other team wants to hire the candidate. Which makes sense from perspective of all. But you can't "veto" to hire which makes no sense.
Source: Am bar raiser.
While bar raisers can't make hiring managers take a candidate they don't want, they can absolutely "veto to hire" for Amazon.
It just means that Recruiting needs to find another team, which the candidate is not guaranteed to be interested in. And that team's manager will also want to interview the candidate, so an offer is not guaranteed again.